Adds manifest_enabled for local/native connections so directory
namespace manifests can be the source of truth, including migration from
directory listing and Azure credential vending feature wiring. Also
exposes the option through Rust, Python, and Node bindings with focused
validation.
This follows the Rust-side Tantivy removal by deleting the remaining
Python Tantivy runtime, tests, and packaging references.
It also turns the legacy Python-only Tantivy parameters into explicit
errors and stops reading legacy `_indices/fts` directories so Python FTS
is fully native-only.
So far, I have been using a hacky approach that creates and opens
namespace-backed table, by getting its location and use a temporary
lancedb connection to create or open it. This was working for features
like credentials vending but is no longer fully working for the managed
versioning feature, recently geneva tests have been failing here and
there and various patches are not addressing the root cause. This PR
fully fixes this and implements proper rust binding for it.
Specifically:
- build a real Rust namespace-backed connection from the Python
namespace client
- route namespace table create/open through that connection instead of
resolved-location temp connections
- keep namespace client naming consistent in the Rust bridge and
preserve federated namespace + DuckDB behavior
## Summary
- pass `namespace_client` through the Python create-table path
- ensure schema-only namespace table creation uses the namespace-aware
empty-table flow
- fix reopening namespace tables created without initial data
## Summary
- delegate child-namespace `ListingDatabase` operations through an
eagerly initialized `LanceNamespaceDatabase`
- support nested namespace create/open/list/drop flows without requiring
callers to inject explicit locations
- add `namespace_client_properties` plumbing for local and namespace
connections so directory namespace settings like
`table_version_tracking_enabled` can be configured
- add regression tests for nested namespace ops and namespace client
property propagation
## Summary
Add connection serialization and child namespace support to
`LanceDBConnection`.
- `DBConnection.serialize()` / `lancedb.deserialize()` for connection
reconstruction in remote workers
- Cache `namespace_client()` in `LanceDBConnection` to avoid repeated
DirectoryNamespace builds
- `LanceDBConnection` transparently delegates child namespace operations
(open_table, create_table, list_tables, drop_table, create_namespace,
etc.) to `LanceNamespaceDBConnection` via `_namespace_conn()`
- Root namespace operations still go through the original Rust path
- Generic worker property override mechanism: any
`namespace_client_properties` key prefixed with `_lancedb_worker_` has
the prefix stripped and overrides the corresponding property when
`deserialize(data, for_worker=True)`
- `LanceNamespaceDBConnection` stores
`namespace_client_impl`/`namespace_client_properties` for serialization
roundtrip
---------
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
## Summary
- migrate gemini-text embedding provider from deprecated
google.generativeai to google.genai
- update Python embedding extra dependency to google-genai
- update default model name to gemini-embedding-001
- adapt embed calls to Client().models.embed_content(...)
- apply lint fixes from CI
## Related
- Closes#3191
`.get(b"split_names", None).decode()` was called unconditionally in both
Permutations.__init__ and Permutation.from_tables(), crashing with
AttributeError when schema metadata existed but lacked the split_names
key. Guard the decode behind a None check and add regression tests.
## Problem
`on_bad_vectors="drop"` is supposed to remove invalid vector rows before
write, but for some schema-defined vector columns it can still fail
later during Arrow cast instead of dropping the bad row.
Repro:
```python
class MySchema(LanceModel):
text: str
embedding: Vector(16)
table = db.create_table("test", schema=MySchema)
table.add(
[
{"text": "hello", "embedding": []},
{"text": "bar", "embedding": [0.1] * 16},
],
on_bad_vectors="drop",
)
```
Before:
```
RuntimeError
Arrow error: C Data interface error: Invalid: ListType can only be casted to FixedSizeListType if the lists are all the expected size.
```
After:
```
rows 1
texts ['bar']
```
## Solution
Make bad-vector sanitization use schema dimensions before cast, while
keeping the handling scoped to vector columns identified by schema
metadata or existing vector-name heuristics.
This also preserves existing integer vector inputs and avoids applying
on_bad_vectors to unrelated fixed-size float columns.
Fixes#1670
Signed-off-by: yaommen <myanstu@163.com>
## Summary
- Add a `user_id` field to `ClientConfig` that allows users to identify
themselves to LanceDB Cloud/Enterprise
- The user_id is sent as the `x-lancedb-user-id` HTTP header in all
requests
- Supports three configuration methods:
- Direct assignment via `ClientConfig.user_id`
- Environment variable `LANCEDB_USER_ID`
- Indirect env var lookup via `LANCEDB_USER_ID_ENV_KEY`
Closes#3230🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
## Summary
Fixes#1846.
Python `Enum` fields raised `TypeError: Converting Pydantic type to
Arrow Type: unsupported type <enum 'SomethingTypes'>` when converting a
Pydantic model to an Arrow schema.
The fix adds Enum detection in `_pydantic_type_to_arrow_type`. When an
Enum subclass is encountered, the value type of its members is inspected
and mapped to the appropriate Arrow type:
- `str`-valued enums (e.g. `class Status(str, Enum)`) → `pa.utf8()`
- `int`-valued enums (e.g. `class Priority(int, Enum)`) → `pa.int64()`
- Other homogeneous value types → the Arrow type for that Python type
- Mixed-value or empty enums → `pa.utf8()` (safe fallback)
This covers the common `(str, Enum)` and `(int, Enum)` mixin patterns
used in practice.
## Changes
- `python/python/lancedb/pydantic.py`: add Enum branch in
`_pydantic_type_to_arrow_type`
- `python/python/tests/test_pydantic.py`: add `test_enum_types` covering
`str`, `int`, and `Optional` Enum fields
## Note on #2395
PR #2395 handles `StrEnum` (Python 3.11+) specifically, using a
dictionary-encoded type. This PR handles the broader `(str, Enum)` /
`(int, Enum)` mixin pattern that works across all Python versions and
stores values as their natural Arrow type.
AI assistance was used in developing this fix.
1. Refactored every client (Rust core, Python, Node/TypeScript) so
“namespace” usage is explicit: code now keeps namespace paths
(namespace_path) separate from namespace clients (namespace_client).
Connections propagate the client, table creation routes through it, and
managed versioning defaults are resolved from namespace metadata. Python
gained LanceNamespaceDBConnection/async counterparts, and the
namespace-focused tests were rewritten to match the clarified API
surface.
2. Synchronized the workspace with Lance 5.0.0-beta.3 (see
https://github.com/lance-format/lance/pull/6186 for the upstream
namespace refactor), updating Cargo/uv lockfiles and ensuring all
bindings align with the new namespace semantics.
3. Added a namespace-backed code path to lancedb.connect() via new
keyword arguments (namespace_client_impl, namespace_client_properties,
plus the existing pushdown-ops flag). When those kwargs are supplied,
connect() delegates to connect_namespace, so users can opt into
namespace clients without changing APIs. (The async helper will gain
parity in a later change)
The test added in #3190 unconditionally imports `PIL`, which is an
optional dependency. This causes CI failures in environments where
Pillow isn't installed (`ModuleNotFoundError: No module named 'PIL'`).
Use `pytest.importorskip` to skip gracefully when Pillow is unavailable.
Fixes CI failure on main.
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
## Summary
- Namespace tests expected `RuntimeError` for table-not-found and
namespace-not-empty cases, but `lance_namespace` raises
`TableNotFoundError` and `NamespaceNotEmptyError` which inherit from
`Exception`, not `RuntimeError`.
- Updated `pytest.raises` to use the correct exception types.
## Test plan
- [x] CI passes on `test_namespace.py`
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
url_retrieve() calls urllib.request.urlopen() but only urllib.error was
imported, causing AttributeError for any HTTP URL input. This affects
open-clip, siglip, and jinaai embedding functions when processing image
URLs.
The bug has existed since the embeddings API refactor (#580) but was
masked because most users pass local file paths or bytes rather than
HTTP URLs.
Fixes#3183
## Summary
When `table.add(mode='overwrite')` is called, PyArrow infers input data
types (e.g. `list<double>`) which differ from the original table schema
(e.g. `fixed_size_list<float32>`). Previously, overwrite mode bypassed
`cast_to_table_schema()` entirely, so the inferred types replaced the
original schema, breaking vector search.
This fix builds a merged target schema for overwrite: columns present in
the existing table schema keep their original types, while columns
unique to the input pass through as-is. This way
`cast_to_table_schema()` is applied unconditionally, preserving vector
column types without blocking schema evolution.
## Changes
- `rust/lancedb/src/table/add_data.rs`: For overwrite mode, construct a
target schema by matching input columns against the existing table
schema, then cast. Non-overwrite (append) path is unchanged.
- Added `test_add_overwrite_preserves_vector_type` test that creates a
table with `fixed_size_list<float32>`, overwrites with `list<double>`
input, and asserts the original type is preserved.
## Test Plan
- `cargo test --features remote -p lancedb -- test_add_overwrite` — all
4 overwrite tests pass
- Full suite: 454 passed, 2 failed (pre-existing `remote::retry` flakes
unrelated to this change)
---------
Signed-off-by: majiayu000 <1835304752@qq.com>
dict.update() mutates in place and returns None. Assigning its result
caused with_metadata(None) to strip all schema metadata when embedding
metadata was merged during create_table with embedding_functions.
## Summary
Adds progress reporting for `table.add()` so users can track large write
operations. The progress callback is available in Rust, Python (sync and
async), and through the PyO3 bindings.
### Usage
Pass `progress=True` to get an automatic tqdm bar:
```python
table.add(data, progress=True)
# 100%|██████████| 1000000/1000000 [00:12<00:00, 82345 rows/s, 45.2 MB/s | 4/4 workers]
```
Or pass a tqdm bar for more control:
```python
from tqdm import tqdm
with tqdm(unit=" rows") as pbar:
table.add(data, progress=pbar)
```
Or use a callback for custom progress handling:
```python
def on_progress(p):
print(f"{p['output_rows']}/{p['total_rows']} rows, "
f"{p['active_tasks']}/{p['total_tasks']} workers, "
f"done={p['done']}")
table.add(data, progress=on_progress)
```
In Rust:
```rust
table.add(data)
.progress(|p| println!("{}/{:?} rows", p.output_rows(), p.total_rows()))
.execute()
.await?;
```
### Details
- `WriteProgress` struct in Rust with getters for `elapsed`,
`output_rows`, `output_bytes`, `total_rows`, `active_tasks`,
`total_tasks`, and `done`. Fields are private behind getters so new
fields can be added without breaking changes.
- `WriteProgressTracker` tracks progress across parallel write tasks
using a mutex for row/byte counts and atomics for active task counts.
- Active task tracking uses an RAII guard pattern (`ActiveTaskGuard`)
that increments on creation and decrements on drop.
- For remote writes, `output_bytes` reflects IPC wire bytes rather than
in-memory Arrow size. For local writes it uses in-memory Arrow size as a
proxy (see TODO below).
- tqdm postfix displays throughput (MB/s) and worker utilization
(active/total).
- The `done` callback always fires, even on error (via `FinishOnDrop`),
so progress bars are always finalized.
### TODO
- Track actual bytes written to disk for local tables. This requires
Lance to expose a progress callback from its write path. See
lance-format/lance#6247.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
## Problem
The generated Python API docs for
`lancedb.table.IndexStatistics.index_type` were misleading because
mkdocstrings renders that field’s type annotation directly, and the
existing `Literal[...]` listed only a subset of the actual canonical SDK
index type strings.
Current (missing index types):
<img width="823" height="83" alt="image"
src="https://github.com/user-attachments/assets/f6f29fe3-4c16-4d00-a4e9-28a7cd6e19ec"
/>
## Fix
- Update the `IndexStatistics.index_type` annotation in
`python/python/lancedb/table.py` to include the full supported set of
canonical values, so the generated docs show all valid index_type
strings inline.
- Add a small regression test in `python/python/tests/test_index.py` to
ensure the docs-facing annotation does not drift silently again in case
we add a new index/quantization type in the future.
- Bumps mkdocs and material theme versions to mkdocs 1.6 to allow access
to more features like hooks
After fix (all index types are included and tested for in the
annotations):
<img width="1017" height="93" alt="image"
src="https://github.com/user-attachments/assets/66c74d5c-34b3-4b44-8173-3ee23e3648ac"
/>
When using hybrid search with a where filter, the prefilter argument is
silently inverted. Passing prefilter=True actually performs
post-filtering, and prefilter=False actually performs pre-filtering.
## Summary
- Removes the "Experimental API" section from `optimize` method
documentation across Rust, Python, and TypeScript
- Adds a warning to `delete_unverified` documentation in all bindings:
this should only be set to true if you can guarantee no other process is
working on the dataset, otherwise it could be corrupted
- Fixes a typo ("shoudl" → "should")
Closes#3125🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
## Summary
- Implement `RemoteTable.prewarm_data(columns)` calling `POST
/v1/table/{id}/page_cache/prewarm/`
- Implement `RemoteTable.prewarm_index(name)` calling `POST
/v1/table/{id}/index/{name}/prewarm/` (previously returned
`NotSupported`)
- Add `BaseTable::prewarm_data(columns)` trait method and `Table` public
API in Rust core
- Add PyO3 bindings and Python API (`AsyncTable`, `LanceTable`,
`RemoteTable`) for `prewarm_data`
- Add type stubs for `prewarm_index` and `prewarm_data` in
`_lancedb.pyi`
- Upgrade Lance to 3.0.0-rc.3 with breaking change fixes
Co-authored-by: Will Jones <willjones127@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Without this fix, if user directly use the native table to do operations
like `add_columns`, even if it is configured to use namespace db
connection, it is not really propagated through.
The fix is to bring lancedb's python binding up to date and do a similar
implementation as https://github.com/lance-format/lance/pull/5968, and
make sure the namespace is fully propagated through all the related
calls.
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
When we write data with `add()`, we can input data to the table's
schema. However, we were using "safe" mode, which propagates errors as
nulls. For example, if you pass `u64::max` into a field that is a `u32`,
it will just write null instead of giving overflow error. Now it
propagates the overflow. This is the same behavior as other systems like
DuckDB.
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
## Summary
- Add `@value_to_sql.register(dict)` handler that converts Python dicts
to DataFusion's `named_struct()` SQL syntax
- Enables updating struct-typed columns via `table.update(values={"col":
{"field_a": 1, "field_b": "hello"}})`
- Recursively handles nested structs, lists, nulls, and all existing
scalar types
Closes#1363
## Details
The `named_struct` function was introduced in DataFusion 38 and is now
available (LanceDB uses DataFusion 52.1). The implementation follows the
existing `singledispatch` pattern in `util.py`.
**Example conversion:**
```python
value_to_sql({"field_a": 1, "field_b": "hello"})
# => "named_struct('field_a', 1, 'field_b', 'hello')"
```
## Test plan
- [x] Unit tests for flat struct, nested struct, list inside struct,
mixed types, null values, and empty dict
- [ ] CI integration tests with actual table.update() on struct columns
🔗 [DataFusion named_struct
docs](https://datafusion.apache.org/user-guide/sql/scalar_functions.html#named-struct)
We don't necessarily need to do this, but one user was confused having
used `fast_search=True` as a keyword argument for vector searches, but
being unable to do so for FTS, even after the most recent changes. I
think this is the only discrepancy in where that is possible.
This hooks up a new writer implementation for the `add()` method. The
main immediate benefit is it allows streaming requests to remote tables,
and at the same time allowing retries for most inputs.
In NodeJS, we always convert the data to `Vec<RecordBatch>`, so it's
always retry-able.
For Python, all are retry-able, except `Iterator` and
`pa.RecordBatchReader`, which can only be consumed once. Some, like
`pa.datasets.Dataset` are retry-able *and* streaming.
A lot of the changes here are to make the new DataFusion write pipeline
maintain the same behavior as the existing Python-based preprocessing,
such as:
* casting input data to target schema
* rejecting NaN values if `on_bad_vectors="error"`
* applying embedding functions.
In future PRs, we'll enhance these by moving the embedding calls into
DataFusion and making sure we parallelize them. See:
https://github.com/lancedb/lancedb/issues/3048
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
## Summary
Fixes#1679
This PR prevents the OpenAI embedding function from retrying when
receiving a 401 Unauthorized error. Authentication errors are permanent
failures that won't be fixed by retrying, yet the current implementation
retries all exceptions up to 7 times by default.
## Changes
- Modified `retry_with_exponential_backoff` in `utils.py` to check for
non-retryable errors before retrying
- Added `_is_non_retryable_error` helper function that detects:
- Exceptions with name `AuthenticationError` (OpenAI's 401 error)
- Exceptions with `status_code` attribute of 401 or 403
- Enhanced OpenAI embeddings to explicitly catch and re-raise
`AuthenticationError` with better logging
- Added unit test `test_openai_no_retry_on_401` to verify authentication
errors don't trigger retries
## Test Plan
- Added test that verifies:
1. A function raising `AuthenticationError` is only called once
2. No retry delays occur (sleep is never called)
- Existing tests continue to pass
- Formatting applied via `make format`
## Example Behavior
**Before**: With an invalid API key, users would see 7 retry attempts
over ~2 minutes:
```
WARNING:root:Error occurred: Error code: 401 - {'error': {'message': 'Incorrect API key provided...'}}
Retrying in 3.97 seconds (retry 1 of 7)
WARNING:root:Error occurred: Error code: 401...
Retrying in 7.94 seconds (retry 2 of 7)
...
```
**After**: With an invalid API key, the error is raised immediately:
```
ERROR:root:Authentication failed: Invalid API key provided
AuthenticationError: Error code: 401 - {'error': {'message': 'Incorrect API key provided...'}}
```
This provides better UX and prevents unnecessary API calls that would
fail anyway.
---------
Co-authored-by: Will Jones <willjones127@gmail.com>
There are old and outdated files in our embedding registry that can
confuse coding agents. This PR deprecates the following files that have
newer, more modern methods to generate such embeddings.
- Deprecate `embeddings/siglip.py`
- Deprecate `embeddings/gte.py`
## Why this change?
Per a discussion with @AyushExel, the [embedding registry directory
](1840aa7edc/python/python/lancedb/embeddings)
in the LanceDB repo has a number of outdated files that need to be
deprecated.
See https://github.com/lancedb/docs/issues/85 for the docs gaps that
identified this.
- Add note in `openclip` docs that it can be used for SigLip embeddings,
which it now supports
- Add note in the `sentence-transformers` page that ALL text embedding
models on Hugging Face can be used
## Problem
When applying hard filters that result in zero matches, hybrid search
crashes with `IndexError: list index out of range` during reranking.
This happens because empty result tables are passed through the full
reranker pipeline, which expects at least one result.
Traceback from the issue:
```
lancedb/query.py: in _combine_hybrid_results
results = reranker.rerank_hybrid(fts_query, vector_results, fts_results)
lancedb/rerankers/answerdotai.py: in rerank_hybrid
combined_results = self._rerank(combined_results, query)
...
IndexError: list index out of range
```
## Fix
Added an early return in `_combine_hybrid_results` when both vector and
FTS results are empty. Instead of passing empty tables through
normalization, reranking, and score restoration (which can fail in
various ways), we now build a properly-typed empty result table with the
`_relevance_score` column and return it directly.
## Test
Added `test_empty_hybrid_result_reranker` that exercises
`_combine_hybrid_results` directly with empty vector and FTS tables,
verifying:
- Returns empty table with correct schema
- Includes `_relevance_score` column
- Respects `with_row_ids` flag
Closes#2425
This changes around the output format of `Permutation` in some breaking
ways but I think the API is still new enough to be considered
experimental.
1. In order to align with both huggingface's dataset and torch's
expectations the default output format is now a list of dicts
(row-major) instead of a dict of lists (column-major). I've added a
python_col option which will return the dict of lists.
2. In order to align with pytorch's expectation the `torch` format is
now a list of tensors (row-major) instead of a 2D tensor (column-major).
I've added a torch_col option which will return the 2D tensor instead.
Added tests for torch integration with Permutation
~~Leaving draft until https://github.com/lancedb/lancedb/pull/3013
merges as this is built on top of that~~
Closes#3000
The hybrid search `explain_plan` now shows the reranker as the top-level
node with
the vector and FTS sub-plans indented underneath, instead of just
listing them
separately with no reranker context.
**Before:**
```
Vector Search Plan:
ProjectionExec: ...
FTS Search Plan:
ProjectionExec: ...
```
**After:**
```
RRFReranker(K=60)
Vector Search Plan:
ProjectionExec: ...
FTS Search Plan:
ProjectionExec: ...
```
Other rerankers display similarly ; e.g.
`LinearCombinationReranker(weight=0.7, fill=1.0)`,
`MRRReranker(weight_vector=0.5, weight_fts=0.5)`,
`CohereReranker(model_name=name)`.
---------
Signed-off-by: dask-58 <googldhruv@gmail.com>
Co-authored-by: Will Jones <willjones127@gmail.com>
Fixes#2999
The error message previously said `"field_names must be a string when
use_tantivy=False"` implying they should use the to be deprecated
tantivy backend #2998.
Updated the error message and docstring to instead guide users to create
a separate FTS index for each field
Signed-off-by: dask-58 <googldhruv@gmail.com>
Expose `initial_storage_options()` and `latest_storage_options()` in
lance Dataset, in lancedb rust, python and typescript SDKs.
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Fixes#2612
This PR exposes the private _fast_search attribute via a public
fast_search() method in the synchronous LanceVectorQueryBuilder.
Previously, enabling fast search in the sync API required accessing a
private member (query._fast_search = True). This change aligns the
synchronous API with the Async and Remote APIs, allowing for cleaner,
more Pythonic method chaining.
Changes:
Added fast_search() method to LanceVectorQueryBuilder in
python/python/lancedb/query.py.
Added a unit test verifying the flag works with high-dimensional data
(2560 dims) and chaining.
Example Usage:
Before:
```
query = table.search(vector)
query._fast_search = True # Private attribute usage
results = query.limit(10).to_pandas()
```
After:
```
results = (
table.search(vector)
.fast_search()
.limit(10)
.to_pandas()
)
```
Verification:
I have added a test case (test_fast_search_high_dimension) that
replicates the scenario described in the issue (2560 dimensions, cosine
distance) to ensure the pipeline constructs the query correctly without
errors.
Checklist:
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.
- [ ] Documentation has been updated (inline docstrings).
Signed-off-by: Rashidul Islam <rasidulislam71@gmail.com>
## Summary
- PR #2957 changed the permutation builder to only select `_rowid` from
the base table, but `Splitter::project()` for hash and calculated splits
replaced the selection entirely, dropping `_rowid`.
- Include `_rowid` in the column selections for hash and calculated
split projections.
- Fix a Python test that queried the permutation table for base table
columns no longer materialized.
Fixes the `test_split_hash`, `test_split_hash_with_discard`,
`test_split_calculated`, `test_shuffle_combined_with_splits`, and
`test_filter_with_splits` failures in `test_permutation.py`.
## Test plan
- [x] `cargo test -p lancedb -- permutation` (22 passed)
- [x] `pytest python/tests/test_permutation.py` (46 passed)
- [x] `npm test __test__/permutation.test.ts` (20 passed)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Fixes#2898
Problem:
Sync API cancellations didn’t stop remote query coroutines, so requests
could continue after interrupt.
Changes:
- Cancel run_coroutine_threadsafe futures on any BaseException in the
sync background loop
- Update cancellation test to avoid starting a real background thread
and cover GeneratorExit
Importing `PIL` alone does not guarantee that the `Image` submodule is
loaded. In a clean environment where no other code has imported
`PIL.Image` before, `PIL.Image` does not exist on the `PIL` package,
which leads to the AttributeError.
