What causes "module {__name__!r} has no attribute {name!r}" in pola-rs/polars?

Fix the typo — confirm the exact public name with `hasattr(pl, 'read_csv')` or the API reference

module {name!r} has no attribute {name!r}

Error message

module {__name__!r} has no attribute {name!r}

What it means

Raised by the module-level __getattr__ (PEP 562) of the polars package: the accessed name is not a real attribute of the top-level `polars` namespace, and it is also not one of the deprecated re-exports (exceptions accessible at top-level, or dtype groups from polars.datatypes.group) which would have returned a deprecation warning instead. Polars only resolves known deprecated aliases here; everything else raises a plain AttributeError naming the module and the missing attribute.

Source

Thrown at py-polars/src/polars/__init__.py:560

            )
            return getattr(exceptions, name)

        # Deprecate data type groups at top-level
        import polars.datatypes.group as dtgroup

        if name in dir(dtgroup):
            from polars._utils.deprecation import issue_deprecation_warning

            issue_deprecation_warning(
                message=(
                    f"`{name}` was deprecated in version 1.0.0. Define your own data type groups or "
                    "use the `polars.selectors` module for selecting columns of a certain data type."
                ),
            )
            return getattr(dtgroup, name)

        msg = f"module {__name__!r} has no attribute {name!r}"
        raise AttributeError(msg)

View on GitHub (pinned to df599052da)

Solutions

Fix the typo — confirm the exact public name with `hasattr(pl, 'read_csv')` or the API reference
If it was a top-level exception (e.g. `pl.NotFoundError`), import it from `polars.exceptions` instead
If it was a dtype group (INTEGER, FLOAT, TEMPORAL, ...), replace with `polars.selectors` (e.g. `cs.integer()`) or define your own group of dtypes
If the API disappeared entirely, check the polars changelog / 1.0 upgrade guide for the new location

Example fix

// before
import polars as pl
df = pl.read_cvs("data.csv")  # AttributeError: module 'polars' has no attribute 'read_cvs'

// after
import polars as pl
df = pl.read_csv("data.csv")

// before (deprecated group path)
pl.NUMERIC_TYPES  # warns, but works

// after
import polars.selectors as cs
df.select(cs.numeric())

Defensive patterns

Strategy: validation

Validate before calling

import polars as pl

name = "read_csv"  # attribute you plan to use
if not hasattr(pl, name):
    raise RuntimeError(f"polars {pl.__version__} has no attribute {name!r} — check spelling/API version")
fn = getattr(pl, name)

Type guard

from typing import Any
import polars as pl

def has_polars_attr(name: str) -> bool:
    """True if the top-level polars namespace exposes `name` (PEP 562 aware)."""
    return hasattr(pl, name)

Try / catch

try:
    fn = getattr(pl, name)
except AttributeError as e:
    # name may be a deprecated alias that still resolves via __getattr__ with a warning,
    # so only treat genuine absence as failure
    raise MyAppConfigError(f"unsupported polars API: {name}") from e

Prevention

Pin the polars version and write code against that version's API docs
Resolve API handles once at startup (module constants) so typos fail fast in one place
For exception classes import from polars.exceptions; for dtype groups use polars.selectors instead of top-level names
Run a quick `hasattr(pl, '...')` guard when calling dynamically-named APIs

When it happens

Trigger: Accessing any misspelled or nonexistent name on `pl`, e.g. `pl.read_cvs(...)`, `pl.data_frame(...)`, `pl.ArrowTypes`; or calling an API that was removed/moved rather than deprecated (top-level exception access moved to polars.exceptions in 1.0, dtype groups like INTEGER/TEMPORAL deprecated in 1.0).

Common situations: Typos picked up from autocomplete; code written for polars 0.x run under 1.x where names moved into submodules (`polars.exceptions`, `polars.selectors`, `polars.datatypes.group`); using a DataFrame/Series method as if it were a module-level function (`pl.shape`, `pl.columns`).

Related errors

AI-assisted analysis of pola-rs/polars@df599052da (2026-08-16). Data as JSON: /api/errors/29a8c8a7eeb95648. Report an issue: GitHub.