Drop support for Python 3.9, require Python >= 3.10

.github/workflows/build_lint.yml

@@ -37,8 +37,6 @@ jobs:
             python-version: "3.11"
           - os: ubuntu
             python-version: "3.10"
-          - os: ubuntu
-            python-version: "3.9"
           # Disabled for now. See https://github.com/projectmesa/mesa/issues/1253
           #- os: ubuntu
           #  python-version: 'pypy-3.8'

.pre-commit-config.yaml

@@ -17,7 +17,7 @@ repos:
     rev: v3.15.2
     hooks:
     -   id: pyupgrade
-        args: [--py38-plus]
+        args: [--py310-plus]
 -   repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v4.5.0  # Use the ref you want to point at
     hooks:

docs/tutorials/intro_tutorial.ipynb

@@ -60,7 +60,7 @@
    "source": [
     "### Tutorial Setup\n",
     "\n",
-    "Create and activate a [virtual environment](http://docs.python-guide.org/en/latest/dev/virtualenvs/). *Python version 3.9 or higher is required*.\n",
+    "Create and activate a [virtual environment](http://docs.python-guide.org/en/latest/dev/virtualenvs/). *Python version 3.10 or higher is required*.\n",
     "\n",
     "Install Mesa:\n",
     "\n",

mesa/agent.py

@@ -14,11 +14,11 @@
 import warnings
 import weakref
 from collections import defaultdict
-from collections.abc import Iterable, Iterator, MutableSet, Sequence
+from collections.abc import Callable, Iterable, Iterator, MutableSet, Sequence
 from random import Random
 
 # mypy
-from typing import TYPE_CHECKING, Any, Callable
+from typing import TYPE_CHECKING, Any
 
 if TYPE_CHECKING:
     # We ensure that these are not imported during runtime to prevent cyclic

mesa/batchrunner.py

@@ -2,7 +2,7 @@
 from collections.abc import Iterable, Mapping
 from functools import partial
 from multiprocessing import Pool
-from typing import Any, Optional, Union
+from typing import Any
 
 from tqdm.auto import tqdm
 
@@ -11,9 +11,9 @@
 
 def batch_run(
     model_cls: type[Model],
-    parameters: Mapping[str, Union[Any, Iterable[Any]]],
+    parameters: Mapping[str, Any | Iterable[Any]],
     # We still retain the Optional[int] because users may set it to None (i.e. use all CPUs)
-    number_processes: Optional[int] = 1,
+    number_processes: int | None = 1,
     iterations: int = 1,
     data_collection_period: int = -1,
     max_steps: int = 1000,
@@ -76,7 +76,7 @@ def batch_run(
 
 
 def _make_model_kwargs(
-    parameters: Mapping[str, Union[Any, Iterable[Any]]],
+    parameters: Mapping[str, Any | Iterable[Any]],
 ) -> list[dict[str, Any]]:
     """Create model kwargs from parameters dictionary.
 

mesa/datacollection.py

@@ -196,7 +196,7 @@ def collect(self, model):
         if self.model_reporters:
             for var, reporter in self.model_reporters.items():
                 # Check if lambda or partial function
-                if isinstance(reporter, (types.LambdaType, partial)):
+                if isinstance(reporter, types.LambdaType | partial):
                     self.model_vars[var].append(reporter(model))
                 # Check if model attribute
                 elif isinstance(reporter, str):

mesa/experimental/cell_space/cell_collection.py

@@ -1,10 +1,10 @@
 from __future__ import annotations
 
 import itertools
-from collections.abc import Iterable, Mapping
+from collections.abc import Callable, Iterable, Mapping
 from functools import cached_property
 from random import Random
-from typing import TYPE_CHECKING, Callable, Generic, TypeVar
+from typing import TYPE_CHECKING, Generic, TypeVar
 
 if TYPE_CHECKING:
     from mesa.experimental.cell_space.cell import Cell

mesa/experimental/cell_space/grid.py

@@ -60,7 +60,7 @@ def _validate_parameters(self):
             raise ValueError("Dimensions must be a list of positive integers.")
         if not isinstance(self.torus, bool):
             raise ValueError("Torus must be a boolean.")
-        if self.capacity is not None and not isinstance(self.capacity, (float, int)):
+        if self.capacity is not None and not isinstance(self.capacity, float | int):
             raise ValueError("Capacity must be a number or None.")
 
     def select_random_empty_cell(self) -> T:

mesa/experimental/cell_space/network.py

@@ -1,5 +1,5 @@
 from random import Random
-from typing import Any, Optional
+from typing import Any
 
 from mesa.experimental.cell_space.cell import Cell
 from mesa.experimental.cell_space.discrete_space import DiscreteSpace
@@ -11,8 +11,8 @@ class Network(DiscreteSpace):
     def __init__(
         self,
         G: Any,  # noqa: N803
-        capacity: Optional[int] = None,
-        random: Optional[Random] = None,
+        capacity: int | None = None,
+        random: Random | None = None,
         cell_klass: type[Cell] = Cell,
     ) -> None:
         """A Networked grid

mesa/experimental/components/altair.py

@@ -1,5 +1,4 @@
 import contextlib
-from typing import Optional
 
 import solara
 
@@ -8,7 +7,7 @@
 
 
 @solara.component
-def SpaceAltair(model, agent_portrayal, dependencies: Optional[list[any]] = None):
+def SpaceAltair(model, agent_portrayal, dependencies: list[any] | None = None):
     space = getattr(model, "grid", None)
     if space is None:
         # Sometimes the space is defined as model.space instead of model.grid

mesa/experimental/components/matplotlib.py

@@ -1,5 +1,3 @@
-from typing import Optional
-
 import networkx as nx
 import solara
 from matplotlib.figure import Figure
@@ -9,7 +7,7 @@
 
 
 @solara.component
-def SpaceMatplotlib(model, agent_portrayal, dependencies: Optional[list[any]] = None):
+def SpaceMatplotlib(model, agent_portrayal, dependencies: list[any] | None = None):
     space_fig = Figure()
     space_ax = space_fig.subplots()
     space = getattr(model, "grid", None)
@@ -116,7 +114,7 @@ def portray(space):
 
 
 @solara.component
-def PlotMatplotlib(model, measure, dependencies: Optional[list[any]] = None):
+def PlotMatplotlib(model, measure, dependencies: list[any] | None = None):
     fig = Figure()
     ax = fig.subplots()
     df = model.datacollector.get_model_vars_dataframe()
@@ -127,7 +125,7 @@ def PlotMatplotlib(model, measure, dependencies: Optional[list[any]] = None):
         for m, color in measure.items():
             ax.plot(df.loc[:, m], label=m, color=color)
         fig.legend()
-    elif isinstance(measure, (list, tuple)):
+    elif isinstance(measure, list | tuple):
         for m in measure:
             ax.plot(df.loc[:, m], label=m)
         fig.legend()

mesa/experimental/devs/eventlist.py

@@ -1,10 +1,11 @@
 from __future__ import annotations
 
 import itertools
+from collections.abc import Callable
 from enum import IntEnum
 from heapq import heapify, heappop, heappush
 from types import MethodType
-from typing import Any, Callable
+from typing import Any
 from weakref import WeakMethod, ref
 
 

mesa/experimental/devs/simulator.py

@@ -1,7 +1,8 @@
 from __future__ import annotations
 
 import numbers
-from typing import Any, Callable
+from collections.abc import Callable
+from typing import Any
 
 from mesa import Model
 

mesa/model.py

@@ -14,12 +14,12 @@
 from collections import defaultdict
 
 # mypy
-from typing import Any, Union
+from typing import Any
 
 from mesa.agent import Agent, AgentSet
 from mesa.datacollection import DataCollector
 
-TimeT = Union[float, int]
+TimeT = float | int
 
 
 class Model:

mesa/space.py

@@ -23,9 +23,9 @@
 import itertools
 import math
 import warnings
-from collections.abc import Iterable, Iterator, Sequence
+from collections.abc import Callable, Iterable, Iterator, Sequence
 from numbers import Real
-from typing import Any, Callable, TypeVar, Union, cast, overload
+from typing import Any, TypeVar, cast, overload
 from warnings import warn
 
 with contextlib.suppress(ImportError):
@@ -42,12 +42,12 @@
 
 Coordinate = tuple[int, int]
 # used in ContinuousSpace
-FloatCoordinate = Union[tuple[float, float], npt.NDArray[float]]
+FloatCoordinate = tuple[float, float] | npt.NDArray[float]
 NetworkCoordinate = int
 
-Position = Union[Coordinate, FloatCoordinate, NetworkCoordinate]
+Position = Coordinate | FloatCoordinate | NetworkCoordinate
 
-GridContent = Union[Agent, None]
+GridContent = Agent | None
 MultiGridContent = list[Agent]
 
 F = TypeVar("F", bound=Callable[..., Any])

mesa/time.py

@@ -30,14 +30,12 @@
 from collections.abc import Iterable
 
 # mypy
-from typing import Union
-
 from mesa.agent import Agent, AgentSet
 from mesa.model import Model
 
 # BaseScheduler has a self.time of int, while
 # StagedActivation has a self.time of float
-TimeT = Union[float, int]
+TimeT = float | int
 
 
 class BaseScheduler:

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "hatchling.build"
 name = "Mesa"
 description = "Agent-based modeling (ABM) in Python"
 license = { text = "Apache 2.0" }
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 authors = [
   { name = "Project Mesa Team", email = "projectmesa@googlegroups.com" },
 ]
@@ -25,7 +25,6 @@ classifiers = [
   "Topic :: Scientific/Engineering :: Artificial Intelligence",
   "Intended Audience :: Science/Research",
   "Programming Language :: Python :: 3 :: Only",
-  "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
@@ -81,9 +80,9 @@ path = "mesa/__init__.py"
 
 [tool.ruff]
 # See https://github.com/charliermarsh/ruff#rules for error code definitions.
-# Hardcode to Python 3.9.
+# Hardcode to Python 3.10.
 # Reminder to update mesa-examples if the value below is changed.
-target-version = "py39"
+target-version = "py310"
 extend-exclude = ["docs", "build"]
 
 [tool.ruff.lint]