remove python 3.9 deps (#463)

* remove python 3.9 deps

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Fix mypy type checking issues

- Add type assertion in expressions.py to clarify pandas Series type
- Keep necessary type: ignore[assignment] comments in test files where intentional type mismatches are tested
- Remove Python 3.9 from classifiers in pyproject.toml (was part of staged changes)
- Update model.py and expressions.py to use union types with | operator

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

* apply type hint convention for python >= 3.10

* fix: remove type hint ignores

* fix: corrent expected exception in test

* add release note

* fix: resolve remaining mypy type errors in COPT solver

Fix type compatibility issues in solvers.py:
- Convert condition to string for Status.from_termination_condition()
- Ensure legacy_status assignment matches expected str type

Resolves the final mypy errors, completing issue #367.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude <[email protected]>

Author: 3 people

doc/release_notes.rst

@@ -5,8 +5,13 @@ Release Notes
 .. ----------------
 
 
+
 * Improved variable/expression arithmetic methods so that they correctly handle types
 
+**Breaking Changes**
+
+* With this release, the package support for python 3.9 was dropped. It now requires python 3.10 or higher.
+
 Version 0.5.5
 --------------
 

linopy/common.py

@@ -9,10 +9,10 @@
 
 import operator
 import os
-from collections.abc import Generator, Hashable, Iterable, Sequence
+from collections.abc import Callable, Generator, Hashable, Iterable, Sequence
 from functools import partial, reduce, wraps
 from pathlib import Path
-from typing import TYPE_CHECKING, Any, Callable, Generic, TypeVar, overload
+from typing import TYPE_CHECKING, Any, Generic, TypeVar, overload
 from warnings import warn
 
 import numpy as np
@@ -117,7 +117,7 @@ def get_from_iterable(lst: DimsLike | None, index: int) -> Any | None:
     """
     if lst is None:
         return None
-    if isinstance(lst, (Sequence, Iterable)):
+    if isinstance(lst, Sequence | Iterable):
         lst = list(lst)
     else:
         lst = [lst]
@@ -210,7 +210,7 @@ def numpy_to_dataarray(
         return DataArray(arr.item(), coords=coords, dims=dims, **kwargs)
 
     ndim = max(arr.ndim, 0 if coords is None else len(coords))
-    if isinstance(dims, (Iterable, Sequence)):
+    if isinstance(dims, Iterable | Sequence):
         dims = list(dims)
     elif dims is not None:
         dims = [dims]
@@ -250,11 +250,11 @@ def as_dataarray(
         DataArray:
             The converted DataArray.
     """
-    if isinstance(arr, (pd.Series, pd.DataFrame)):
+    if isinstance(arr, pd.Series | pd.DataFrame):
         arr = pandas_to_dataarray(arr, coords=coords, dims=dims, **kwargs)
     elif isinstance(arr, np.ndarray):
         arr = numpy_to_dataarray(arr, coords=coords, dims=dims, **kwargs)
-    elif isinstance(arr, (np.number, int, float, str, bool, list)):
+    elif isinstance(arr, np.number | int | float | str | bool | list):
         arr = DataArray(arr, coords=coords, dims=dims, **kwargs)
 
     elif not isinstance(arr, DataArray):
@@ -493,7 +493,7 @@ def fill_missing_coords(
 
     """
     ds = ds.copy()
-    if not isinstance(ds, (Dataset, DataArray)):
+    if not isinstance(ds, Dataset | DataArray):
         raise TypeError(f"Expected xarray.DataArray or xarray.Dataset, got {type(ds)}.")
 
     skip_dims = [] if fill_helper_dims else HELPER_DIMS
@@ -807,7 +807,7 @@ def print_coord(coord: dict[str, Any] | Iterable[Any]) -> str:
     # Convert each coordinate component to string
     formatted = []
     for value in values:
-        if isinstance(value, (list, tuple)):
+        if isinstance(value, list | tuple):
             formatted.append(f"({', '.join(str(x) for x in value)})")
         else:
             formatted.append(str(value))
@@ -946,11 +946,9 @@ def is_constant(func: Callable[..., Any]) -> Callable[..., Any]:
     def wrapper(self: Any, arg: Any) -> Any:
         if isinstance(
             arg,
-            (
-                variables.Variable,
-                variables.ScalarVariable,
-                expressions.LinearExpression,
-            ),
+            variables.Variable
+            | variables.ScalarVariable
+            | expressions.LinearExpression,
         ):
             raise TypeError(f"Assigned rhs must be a constant, got {type(arg)}).")
         return func(self, arg)
@@ -1061,7 +1059,7 @@ def align(
     finisher: list[partial[Any] | Callable[[Any], Any]] = []
     das: list[Any] = []
     for obj in objects:
-        if isinstance(obj, (LinearExpression, QuadraticExpression)):
+        if isinstance(obj, LinearExpression | QuadraticExpression):
             finisher.append(partial(obj.__class__, model=obj.model))
             das.append(obj.data)
         elif isinstance(obj, Variable):

linopy/constants.py

@@ -169,7 +169,7 @@ class Status:
 
     status: SolverStatus
     termination_condition: TerminationCondition
-    legacy_status: Union[tuple[str, str], str] = ""
+    legacy_status: tuple[str, str] | str = ""
 
     @classmethod
     def process(cls, status: str, termination_condition: str) -> "Status":
@@ -214,7 +214,7 @@ class Result:
     """
 
     status: Status
-    solution: Union[Solution, None] = None
+    solution: Solution | None = None
     solver_model: Any = None
 
     def __repr__(self) -> str:

linopy/constraints.py

@@ -940,7 +940,7 @@ def get_name_by_label(self, label: int | float) -> str:
         name : str
             Name of the containing constraint.
         """
-        if not isinstance(label, (float, int)) or label < 0:
+        if not isinstance(label, float | int) or label < 0:
             raise ValueError("Label must be a positive number.")
         for name, ds in self.items():
             if label in ds.labels:
@@ -1084,7 +1084,7 @@ def __init__(
         """
         Initialize a anonymous scalar constraint.
         """
-        if not isinstance(rhs, (int, float, np.floating, np.integer)):
+        if not isinstance(rhs, int | float | np.floating | np.integer):
             raise TypeError(f"Assigned rhs must be a constant, got {type(rhs)}).")
         self._lhs = lhs
         self._sign = sign

linopy/expressions.py

@@ -39,6 +39,8 @@
     import xarray.core.rolling
     from xarray.core.rolling import DatasetRolling  # type: ignore
 
+from types import EllipsisType, NotImplementedType
+
 from linopy import constraints, variables
 from linopy.common import (
     EmptyDeprecationWrapper,
@@ -77,9 +79,7 @@
 from linopy.types import (
     ConstantLike,
     DimsLike,
-    EllipsisType,
     ExpressionLike,
-    NotImplementedType,
     SideLike,
     SignLike,
     VariableLike,
@@ -129,7 +129,7 @@ def _exprwrap(
 def _expr_unwrap(
     maybe_expr: Any | LinearExpression | QuadraticExpression,
 ) -> Any:
-    if isinstance(maybe_expr, (LinearExpression, QuadraticExpression)):
+    if isinstance(maybe_expr, LinearExpression | QuadraticExpression):
         return maybe_expr.data
 
     return maybe_expr
@@ -249,6 +249,8 @@ def sum(self, use_fallback: bool = False, **kwargs: Any) -> LinearExpression:
                 orig_group = group
                 group = group.apply(tuple, axis=1).map(int_map)
 
+            # At this point, group is always a pandas Series
+            assert isinstance(group, pd.Series)
             group_dim = group.index.name
 
             arrays = [group, group.groupby(group).cumcount()]
@@ -529,13 +531,11 @@ def __div__(self: GenericExpression, other: SideLike) -> GenericExpression:
         try:
             if isinstance(
                 other,
-                (
-                    variables.Variable,
-                    variables.ScalarVariable,
-                    LinearExpression,
-                    ScalarLinearExpression,
-                    QuadraticExpression,
-                ),
+                variables.Variable
+                | variables.ScalarVariable
+                | LinearExpression
+                | ScalarLinearExpression
+                | QuadraticExpression,
             ):
                 raise TypeError(
                     "unsupported operand type(s) for /: "
@@ -930,7 +930,7 @@ def where(
                 _other = FILL_VALUE
             else:
                 _other = None
-        elif isinstance(other, (int, float, DataArray)):
+        elif isinstance(other, int | float | DataArray):
             _other = {**self._fill_value, "const": other}
         else:
             _other = _expr_unwrap(other)
@@ -970,7 +970,7 @@ def fillna(
             A new object with missing values filled with the given value.
         """
         value = _expr_unwrap(value)
-        if isinstance(value, (DataArray, np.floating, np.integer, int, float)):
+        if isinstance(value, DataArray | np.floating | np.integer | int | float):
             value = {"const": value}
         return self.__class__(self.data.fillna(value), self.model)
 
@@ -1362,10 +1362,10 @@ def __mul__(
             return other.__rmul__(self)
 
         try:
-            if isinstance(other, (variables.Variable, variables.ScalarVariable)):
+            if isinstance(other, variables.Variable | variables.ScalarVariable):
                 other = other.to_linexpr()
 
-            if isinstance(other, (LinearExpression, ScalarLinearExpression)):
+            if isinstance(other, LinearExpression | ScalarLinearExpression):
                 return self._multiply_by_linear_expression(other)
             else:
                 return self._multiply_by_constant(other)
@@ -1403,7 +1403,7 @@ def __matmul__(
         """
         Matrix multiplication with other, similar to xarray dot.
         """
-        if not isinstance(other, (LinearExpression, variables.Variable)):
+        if not isinstance(other, LinearExpression | variables.Variable):
             other = as_dataarray(other, coords=self.coords, dims=self.coord_dims)
 
         common_dims = list(set(self.coord_dims).intersection(other.dims))
@@ -1620,7 +1620,7 @@ def process_one(
                 # assume first element is coefficient and second is variable
                 c, v = t
                 if isinstance(v, variables.ScalarVariable):
-                    if not isinstance(c, (int, float)):
+                    if not isinstance(c, int | float):
                         raise TypeError(
                             "Expected int or float as coefficient of scalar variable (first element of tuple)."
                         )
@@ -1703,12 +1703,10 @@ def __mul__(self, other: SideLike) -> QuadraticExpression:
         """
         if isinstance(
             other,
-            (
-                BaseExpression,
-                ScalarLinearExpression,
-                variables.Variable,
-                variables.ScalarVariable,
-            ),
+            BaseExpression
+            | ScalarLinearExpression
+            | variables.Variable
+            | variables.ScalarVariable,
         ):
             raise TypeError(
                 "unsupported operand type(s) for *: "
@@ -1787,12 +1785,10 @@ def __matmul__(
         """
         if isinstance(
             other,
-            (
-                BaseExpression,
-                ScalarLinearExpression,
-                variables.Variable,
-                variables.ScalarVariable,
-            ),
+            BaseExpression
+            | ScalarLinearExpression
+            | variables.Variable
+            | variables.ScalarVariable,
         ):
             raise TypeError(
                 "Higher order non-linear expressions are not yet supported."
@@ -1915,9 +1911,9 @@ def as_expression(
     ValueError
         If object cannot be converted to LinearExpression.
     """
-    if isinstance(obj, (LinearExpression, QuadraticExpression)):
+    if isinstance(obj, LinearExpression | QuadraticExpression):
         return obj
-    elif isinstance(obj, (variables.Variable, variables.ScalarVariable)):
+    elif isinstance(obj, variables.Variable | variables.ScalarVariable):
         return obj.to_linexpr()
     else:
         try:
@@ -2134,7 +2130,7 @@ def __neg__(self) -> ScalarLinearExpression:
         )
 
     def __mul__(self, other: float | int) -> ScalarLinearExpression:
-        if not isinstance(other, (int, float, np.number)):
+        if not isinstance(other, int | float | np.number):
             raise TypeError(
                 f"unsupported operand type(s) for *: {type(self)} and {type(other)}"
             )
@@ -2147,7 +2143,7 @@ def __rmul__(self, other: int) -> ScalarLinearExpression:
         return self.__mul__(other)
 
     def __div__(self, other: float | int) -> ScalarLinearExpression:
-        if not isinstance(other, (int, float, np.number)):
+        if not isinstance(other, int | float | np.number):
             raise TypeError(
                 f"unsupported operand type(s) for /: {type(self)} and {type(other)}"
             )
@@ -2157,23 +2153,23 @@ def __truediv__(self, other: float | int) -> ScalarLinearExpression:
         return self.__div__(other)
 
     def __le__(self, other: int | float) -> AnonymousScalarConstraint:
-        if not isinstance(other, (int, float, np.number)):
+        if not isinstance(other, int | float | np.number):
             raise TypeError(
                 f"unsupported operand type(s) for <=: {type(self)} and {type(other)}"
             )
 
         return constraints.AnonymousScalarConstraint(self, LESS_EQUAL, other)
 
     def __ge__(self, other: int | float) -> AnonymousScalarConstraint:
-        if not isinstance(other, (int, float, np.number)):
+        if not isinstance(other, int | float | np.number):
             raise TypeError(
                 f"unsupported operand type(s) for >=: {type(self)} and {type(other)}"
             )
 
         return constraints.AnonymousScalarConstraint(self, GREATER_EQUAL, other)
 
     def __eq__(self, other: int | float) -> AnonymousScalarConstraint:  # type: ignore
-        if not isinstance(other, (int, float, np.number)):
+        if not isinstance(other, int | float | np.number):
             raise TypeError(
                 f"unsupported operand type(s) for ==: {type(self)} and {type(other)}"
             )

linopy/io.py

@@ -8,11 +8,11 @@
 import logging
 import shutil
 import time
-from collections.abc import Iterable
+from collections.abc import Callable, Iterable
 from io import BufferedWriter, TextIOWrapper
 from pathlib import Path
 from tempfile import TemporaryDirectory
-from typing import TYPE_CHECKING, Any, Callable
+from typing import TYPE_CHECKING, Any
 
 import numpy as np
 import pandas as pd

linopy/matrices.py

@@ -32,7 +32,7 @@ def create_vector(
     """Create a vector of a size equal to the maximum index plus one."""
     if shape is None:
         max_value = indices.max()
-        if not isinstance(max_value, (np.integer, int)):
+        if not isinstance(max_value, np.integer | int):
             raise ValueError("Indices must be integers.")
         shape = max_value + 1
     vector = np.full(shape, fill_value)

linopy/model.py

@@ -317,7 +317,7 @@ def solver_dir(self) -> Path:
 
     @solver_dir.setter
     def solver_dir(self, value: str | Path) -> None:
-        if not isinstance(value, (str, Path)):
+        if not isinstance(value, str | Path):
             raise TypeError("'solver_dir' must path-like.")
         self._solver_dir = Path(value)
 
@@ -614,7 +614,7 @@ def add_constraints(
             if sign is None or rhs is None:
                 raise ValueError(msg_sign_rhs_not_none)
             data = lhs.to_constraint(sign, rhs).data
-        elif isinstance(lhs, (list, tuple)):
+        elif isinstance(lhs, list | tuple):
             if sign is None or rhs is None:
                 raise ValueError(msg_sign_rhs_none)
             data = self.linexpr(*lhs).to_constraint(sign, rhs).data
@@ -633,7 +633,7 @@ def add_constraints(
             if sign is not None or rhs is not None:
                 raise ValueError(msg_sign_rhs_none)
             data = lhs.data
-        elif isinstance(lhs, (Variable, ScalarVariable, ScalarLinearExpression)):
+        elif isinstance(lhs, Variable | ScalarVariable | ScalarLinearExpression):
             if sign is None or rhs is None:
                 raise ValueError(msg_sign_rhs_not_none)
             data = lhs.to_linexpr().to_constraint(sign, rhs).data
@@ -710,7 +710,7 @@ def add_objective(
                 "Objective already defined."
                 " Set `overwrite` to True to force overwriting."
             )
-        self.objective.expression = expr  # type: ignore[assignment]
+        self.objective.expression = expr
         self.objective.sense = sense
 
     def remove_variables(self, name: str) -> None: