Remove Python 3.8 support

.github/workflows/ci-tests.yml

@@ -15,7 +15,7 @@ on:
       - "release/*"
 
 env:
-  DEFAULT_PYTHON: 3.8
+  DEFAULT_PYTHON: 3.9
   CI: "true"
 
 concurrency:
@@ -118,9 +118,6 @@ jobs:
           pip-cache: ~/Library/Caches/pip
         - os: windows-latest
           pip-cache: ~/AppData/Local/pip/Cache
-        exclude:
-        - python-version: "3.8"
-          pandas-version: "2.2.2"
         - python-version: "3.11"
           pandas-version: "1.5.3"
         - python-version: "3.12"

.pre-commit-config.yaml

@@ -41,7 +41,7 @@ repos:
     rev: v3.19.1
     hooks:
       - id: pyupgrade
-        args: [--py38-plus, --keep-runtime-typing]
+        args: [--py39-plus, --keep-runtime-typing]
 
   - repo: https://github.com/pycqa/pylint
     rev: v3.2.7

docs/source/dataframe_models.md

@@ -339,10 +339,8 @@ to python 3.6.
 ✅ Good:
 
 ```{code-cell} python
-try:
-    from typing import Annotated  # python 3.9+
-except ImportError:
-    from typing_extensions import Annotated
+from typing import Annotated
+
 
 class Schema(pa.DataFrameModel):
     col: Series[Annotated[pd.DatetimeTZDtype, "ns", "est"]]

docs/source/dtype_validation.md

@@ -112,10 +112,8 @@ express this same type with the class-based API, we need to use an
 {py:class}`~typing.Annotated` type:
 
 ```{code-cell} python
-try:
-    from typing import Annotated  # python 3.9+
-except ImportError:
-    from typing_extensions import Annotated
+from typing import Annotated
+
 
 class DateTimeModel(pa.DataFrameModel):
     dt: Series[Annotated[pd.DatetimeTZDtype, "ns", "UTC"]]
@@ -266,10 +264,7 @@ And when using class-based API, you must specify actual types (string aliases
 are not supported):
 
 ```{code-cell} python
-try:
-    from typing import Annotated  # python 3.9+
-except ImportError:
-    from typing_extensions import Annotated
+from typing import Annotated
 
 
 class PyarrowModel(pa.DataFrameModel):

docs/source/polars.md

@@ -484,10 +484,8 @@ schema = pa.DataFrameSchema(
 :::{tab-item} DataFrameModel (Annotated)
 
 ```{testcode} polars
-try:
-    from typing import Annotated  # python 3.9+
-except ImportError:
-    from typing_extensions import Annotated
+from typing import Annotated
+
 
 class ModelWithAnnotated(pa.DataFrameModel):
     list_col: Annotated[pl.List, pl.Int64()]

environment.yml

@@ -55,7 +55,6 @@ dependencies:
   - xdoctest
   - nox
   - setuptools # required in noxfile and not automatically provided by python >= 3.12
-  - importlib_metadata # required if python < 3.8
 
   # fastapi testing
   - uvicorn

noxfile.py

@@ -9,8 +9,7 @@
 import re
 import shutil
 import sys
-import tempfile
-from typing import Dict, List
+from typing import Optional
 
 try:
     import tomllib
@@ -53,7 +52,7 @@
 LINE_LENGTH = 79
 
 
-def _build_setup_requirements() -> Dict[str, List[str]]:
+def _build_setup_requirements() -> dict[str, list[str]]:
     """Load requirments from setup.py."""
     # read pyproject.toml to get optional dependencies
 
@@ -74,7 +73,7 @@ def _build_setup_requirements() -> Dict[str, List[str]]:
     }
 
 
-def _build_dev_requirements() -> List[str]:
+def _build_dev_requirements() -> list[str]:
     """Load requirements from file."""
     with open(REQUIREMENT_PATH, encoding="utf-8") as req_file:
         reqs = []
@@ -83,11 +82,11 @@ def _build_dev_requirements() -> List[str]:
         return reqs
 
 
-SETUP_REQUIREMENTS: Dict[str, List[str]] = _build_setup_requirements()
-DEV_REQUIREMENTS: List[str] = _build_dev_requirements()
+SETUP_REQUIREMENTS: dict[str, list[str]] = _build_setup_requirements()
+DEV_REQUIREMENTS: list[str] = _build_dev_requirements()
 
 
-def _build_requires() -> Dict[str, Dict[str, str]]:
+def _build_requires() -> dict[str, list[str]]:
     """Return a dictionary of requirements {EXTRA_NAME: {PKG_NAME:PIP_SPECS}}.
 
     Adds fake extras "core" and "all".
@@ -116,7 +115,7 @@ def _build_requires() -> Dict[str, Dict[str, str]]:
     return requires
 
 
-REQUIRES: Dict[str, Dict[str, str]] = _build_requires()
+REQUIRES = _build_requires()
 
 CONDA_ARGS = [
     "--channel=conda-forge",
@@ -272,11 +271,11 @@ def requirements(session: Session) -> None:  # pylint:disable=unused-argument
 
 def _get_pinned_requirements(
     session: Session, pandas: str, pydantic: str, extra: str
-) -> None:
+) -> list[str]:
     _requirements = REQUIRES["all"]
-    _pinned_requirements = []
+    _pinned_requirements: list[str] = []
 
-    _numpy: str | None = None
+    _numpy: Optional[str] = None
     if pandas != "2.2.2":
         _numpy = "< 2"
 

pandera/api/base/checks.py

@@ -5,16 +5,13 @@
 from typing import (
     Any,
     Callable,
-    Dict,
-    Iterable,
     NamedTuple,
     Optional,
-    Tuple,
-    Type,
     TypeVar,
     Union,
     no_type_check,
 )
+from collections.abc import Iterable
 
 import pandas as pd
 from pandera.api.function_dispatch import Dispatcher
@@ -36,8 +33,8 @@ class CheckResult(NamedTuple):
     pd.core.groupby.generic.DataFrameGroupBy,
 ]
 
-SeriesCheckObj = Union[pd.Series, Dict[str, pd.Series]]
-DataFrameCheckObj = Union[pd.DataFrame, Dict[str, pd.DataFrame]]
+SeriesCheckObj = Union[pd.Series, dict[str, pd.Series]]
+DataFrameCheckObj = Union[pd.DataFrame, dict[str, pd.DataFrame]]
 
 
 _T = TypeVar("_T", bound="BaseCheck")
@@ -46,15 +43,15 @@ class CheckResult(NamedTuple):
 class MetaCheck(type):  # pragma: no cover
     """Check metaclass."""
 
-    BACKEND_REGISTRY: Dict[Tuple[Type, Type], Type[BaseCheckBackend]] = (
+    BACKEND_REGISTRY: dict[tuple[type, type], type[BaseCheckBackend]] = (
         {}
     )  # noqa
     """Registry of check backends implemented for specific data objects."""
 
-    CHECK_FUNCTION_REGISTRY: Dict[str, Dispatcher] = {}  # noqa
+    CHECK_FUNCTION_REGISTRY: dict[str, Dispatcher] = {}  # noqa
     """Built-in check function registry."""
 
-    REGISTERED_CUSTOM_CHECKS: Dict[str, Callable] = {}  # noqa
+    REGISTERED_CUSTOM_CHECKS: dict[str, Callable] = {}  # noqa
     """User-defined custom checks."""
 
     def __getattr__(cls, name: str) -> Any:
@@ -85,7 +82,7 @@ def __dir__(cls) -> Iterable[str]:
     # see https://mypy.readthedocs.io/en/stable/metaclasses.html#gotchas-and-limitations-of-metaclass-support
     # pylint: enable=line-too-long
     @no_type_check
-    def __contains__(cls: Type[_T], item: Union[_T, str]) -> bool:
+    def __contains__(cls: type[_T], item: Union[_T, str]) -> bool:
         """Allow lookups for registered checks."""
         if isinstance(item, cls):
             name = item.name
@@ -102,7 +99,7 @@ def __init__(
         self,
         name: Optional[str] = None,
         error: Optional[str] = None,
-        statistics: Optional[Dict[str, Any]] = None,
+        statistics: Optional[dict[str, Any]] = None,
     ):
         self.name = name
         self.error = error
@@ -136,7 +133,7 @@ def from_builtin_check_name(
         name: str,
         init_kwargs,
         error: Union[str, Callable],
-        statistics: Optional[Dict[str, Any]] = None,
+        statistics: Optional[dict[str, Any]] = None,
         **check_kwargs,
     ):
         """Create a Check object from a built-in check's name."""
@@ -156,13 +153,13 @@ def from_builtin_check_name(
         )
 
     @classmethod
-    def register_backend(cls, type_: Type, backend: Type[BaseCheckBackend]):
+    def register_backend(cls, type_: type, backend: type[BaseCheckBackend]):
         """Register a backend for the specified type."""
         if (cls, type_) not in cls.BACKEND_REGISTRY:
             cls.BACKEND_REGISTRY[(cls, type_)] = backend
 
     @classmethod
-    def get_backend(cls, check_obj: Any) -> Type[BaseCheckBackend]:
+    def get_backend(cls, check_obj: Any) -> type[BaseCheckBackend]:
         """Get the backend associated with the type of ``check_obj`` ."""
 
         check_obj_cls = type(check_obj)

pandera/api/base/error_handler.py

@@ -2,7 +2,7 @@
 
 from collections import defaultdict
 from enum import Enum
-from typing import Any, Dict, List, Union
+from typing import Any, Union
 
 from pandera.api.checks import Check
 from pandera.config import ValidationDepth, get_config_context
@@ -28,8 +28,8 @@ def __init__(self, lazy: bool = True) -> None:
         Defaults to True.
         """
         self._lazy = lazy
-        self._collected_errors: List[Dict[str, Any]] = []
-        self._schema_errors: List[SchemaError] = []
+        self._collected_errors: list[dict[str, Any]] = []
+        self._schema_errors: list[SchemaError] = []
         self._summarized_errors = defaultdict(lambda: defaultdict(list))  # type: ignore
 
     @property
@@ -86,7 +86,7 @@ def collect_error(
 
     def collect_errors(
         self,
-        schema_errors: List[SchemaError],
+        schema_errors: list[SchemaError],
         original_exc: Union[BaseException, None] = None,
     ):
         """Collect schema errors from a SchemaErrors exception.
@@ -104,19 +104,19 @@ def collect_errors(
             )
 
     @property
-    def collected_errors(self) -> List[Dict[str, Any]]:
+    def collected_errors(self) -> list[dict[str, Any]]:
         """Retrieve error objects collected during lazy validation."""
         return self._collected_errors
 
     @collected_errors.setter
-    def collected_errors(self, value: List[Dict[str, Any]]):
+    def collected_errors(self, value: list[dict[str, Any]]):
         """Set the list of collected errors."""
         if not isinstance(value, list):
             raise ValueError("collected_errors must be a list")
         self._collected_errors = value
 
     @property
-    def schema_errors(self) -> List[SchemaError]:
+    def schema_errors(self) -> list[SchemaError]:
         """Retrieve SchemaError objects collected during lazy validation."""
         return self._schema_errors
 

pandera/api/base/model.py

@@ -1,17 +1,8 @@
 """Base classes for model api."""
 
 import os
-from typing import (
-    Any,
-    Dict,
-    List,
-    Mapping,
-    Optional,
-    Tuple,
-    Type,
-    TypeVar,
-    Union,
-)
+from typing import Any, Optional, TypeVar, Union
+from collections.abc import Mapping
 
 from pandera.api.base.model_components import BaseFieldInfo
 from pandera.api.base.model_config import BaseModelConfig
@@ -34,24 +25,24 @@ def __str__(cls):
 class BaseModel(metaclass=MetaModel):
     """Base class for a Data Object Model."""
 
-    Config: Type[BaseModelConfig] = BaseModelConfig
-    __extras__: Optional[Dict[str, Any]] = None
+    Config: type[BaseModelConfig] = BaseModelConfig
+    __extras__: Optional[dict[str, Any]] = None
     __schema__: Optional[Any] = None
-    __config__: Optional[Type[BaseModelConfig]] = None
+    __config__: Optional[type[BaseModelConfig]] = None
 
     #: Key according to `FieldInfo.name`
-    __fields__: Mapping[str, Tuple[AnnotationInfo, BaseFieldInfo]] = {}
-    __checks__: Dict[str, List[Check]] = {}
-    __root_checks__: List[Check] = []
+    __fields__: Mapping[str, tuple[AnnotationInfo, BaseFieldInfo]] = {}
+    __checks__: dict[str, list[Check]] = {}
+    __root_checks__: list[Check] = []
 
     # This is syntantic sugar that delegates to the validate method
     def __new__(cls, *args, **kwargs) -> Any:
         raise NotImplementedError
 
     def __class_getitem__(
-        cls: Type[TBaseModel],
-        params: Union[Type[Any], Tuple[Type[Any], ...]],
-    ) -> Type[TBaseModel]:
+        cls: type[TBaseModel],
+        params: Union[type[Any], tuple[type[Any], ...]],
+    ) -> type[TBaseModel]:
         """
         Parameterize the class's generic arguments with the specified types.
 
@@ -71,7 +62,7 @@ def to_yaml(cls, stream: Optional[os.PathLike] = None):
 
     @classmethod
     def validate(
-        cls: Type[TBaseModel],
+        cls: type[TBaseModel],
         check_obj: Any,
         head: Optional[int] = None,
         tail: Optional[int] = None,
@@ -84,12 +75,12 @@ def validate(
         raise NotImplementedError
 
     @classmethod
-    def strategy(cls: Type[TBaseModel], *, size: Optional[int] = None):
+    def strategy(cls: type[TBaseModel], *, size: Optional[int] = None):
         """Create a data synthesis strategy."""
         raise NotImplementedError
 
     @classmethod
-    def example(cls: Type[TBaseModel], *, size: Optional[int] = None) -> Any:
+    def example(cls: type[TBaseModel], *, size: Optional[int] = None) -> Any:
         """Generate an example of this data model specification."""
         raise NotImplementedError