create a minimal pufferlib-core package

packages/pufferlib-core/README.md

@@ -0,0 +1,10 @@
+# PufferLib Core
+
+Minimal PufferLib core functionality with vectorized environments.
+
+This package contains only the essential components:
+- `spaces`: Observation/action space handling
+- `emulation`: Environment compatibility layer for Gym/Gymnasium/PettingZoo
+- `vector`: Vectorized environment implementations
+
+For the full PufferLib with training capabilities and environments, see the main `pufferlib` package.

packages/pufferlib-core/pufferlib/__init__.py

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+"""
+PufferLib Core - Minimal vectorized environment functionality
+"""
+
+import sys
+
+# Import individual modules with delayed loading to avoid circular imports
+def _import_modules():
+    from . import spaces
+    from . import pufferlib
+
+    # Temporarily add pufferlib to the current module namespace to resolve imports
+    current_module = sys.modules[__name__]
+    current_module.PufferEnv = pufferlib.PufferEnv
+    current_module.set_buffers = pufferlib.set_buffers
+    current_module.unroll_nested_dict = pufferlib.unroll_nested_dict
+
+    from . import emulation
+    from . import vector
+
+    return spaces, pufferlib, emulation, vector
+
+# Perform the imports
+spaces, pufferlib, emulation, vector = _import_modules()
+
+__version__ = "3.0.3"
+__all__ = ["spaces", "emulation", "vector", "pufferlib"]

packages/pufferlib-core/pufferlib/emulation.py

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+../../../pufferlib/emulation.py

packages/pufferlib-core/pufferlib/pufferlib.py

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+../../../pufferlib/pufferlib.py

packages/pufferlib-core/pufferlib/spaces.py

@@ -0,0 +1 @@
+../../../pufferlib/spaces.py

packages/pufferlib-core/pufferlib/vector.py

@@ -0,0 +1 @@
+../../../pufferlib/vector.py

packages/pufferlib-core/pyproject.toml

@@ -0,0 +1,54 @@
+[build-system]
+requires = ["setuptools>=45", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "pufferlib-core"
+version = "3.0.3"
+description = "Minimal PufferLib core functionality with vectorized environments"
+readme = "README.md"
+requires-python = ">=3.8"
+license = {text = "MIT"}
+authors = [
+    {name = "Joseph Suarez", email = "[email protected]"},
+]
+keywords = [
+    "reinforcement-learning",
+    "machine-learning",
+    "multi-agent",
+    "vectorized-environments",
+]
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Environment :: Console",
+    "Intended Audience :: Developers",
+    "Intended Audience :: Education",
+    "Intended Audience :: Science/Research",
+    "License :: OSI Approved :: MIT License",
+    "Operating System :: OS Independent",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Topic :: Scientific/Engineering :: Artificial Intelligence",
+    "Topic :: Software Development :: Libraries :: Python Modules",
+]
+dependencies = [
+    "numpy",
+    "gymnasium",
+    "psutil"
+]
+
+[project.urls]
+Homepage = "https://github.com/PufferAI/PufferLib"
+Documentation = "https://puffer.ai"
+Repository = "https://github.com/PufferAI/PufferLib"
+Issues = "https://github.com/PufferAI/PufferLib/issues"
+
+[tool.setuptools.packages.find]
+include = ["pufferlib*"]
+
+[tool.setuptools.package-data]
+pufferlib = ["*.py"]

pufferlib/spaces.py

@@ -1,7 +1,12 @@
 import numpy as np
-import gym
 import gymnasium
 
+try:
+    import gym
+except ImportError:
+    # Alias gymnasium as gym when gym is not available
+    gym = gymnasium
+
 Box = (gym.spaces.Box, gymnasium.spaces.Box)
 Dict = (gym.spaces.Dict, gymnasium.spaces.Dict)
 Discrete = (gym.spaces.Discrete, gymnasium.spaces.Discrete)