Provide setup.py as fallback (again)

setup.py

@@ -0,0 +1,69 @@
+# We still provide a setup.py for backwards compatability.
+# But the pyproject.toml should be prefered.
+import itertools
+from pathlib import Path
+from typing import List
+
+from setuptools import setup, find_packages
+
+# Environment-specific dependencies for dmc and metaworld
+extras = {
+    'dmc': ['shimmy[dm-control]', 'Shimmy==1.0.0'],
+    'box2d': ['gymnasium[box2d]>=0.26.0'],
+    'mujoco-legacy': ['mujoco-py >=2.1,<2.2', 'cython<3'],
+    'jax': ["jax >=0.4.0", "jaxlib >=0.4.0"],
+}
+
+# All dependencies
+all_groups = set(extras.keys())
+extras["all"] = list(set(itertools.chain.from_iterable(
+    map(lambda group: extras[group], all_groups))))
+
+extras['testing'] = extras["all"] + ['pytest']
+
+
+def find_package_data(extensions_to_include: List[str]) -> List[str]:
+    envs_dir = Path("fancy_gym/envs/mujoco")
+    package_data_paths = []
+    for extension in extensions_to_include:
+        package_data_paths.extend([str(path)[10:]
+                                  for path in envs_dir.rglob(extension)])
+
+    return package_data_paths
+
+
+setup(
+    author='Fabian Otto, Onur Celik, Dominik Roth, Hongyi Zhou',
+    name='fancy_gym',
+    version='1.0',
+    classifiers=[
+        'Development Status :: 4 - Beta',
+        'Intended Audience :: Science/Research',
+        'License :: OSI Approved :: MIT License',
+        'Natural Language :: English',
+        'Operating System :: OS Independent',
+        'Topic :: Scientific/Engineering :: Artificial Intelligence',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
+        'Programming Language :: Python :: 3.11',
+    ],
+    extras_require=extras,
+    install_requires=[
+        'mp_pytorch<=0.1.3',
+        'mujoco==2.3.3',
+        'gymnasium[mujoco]>=0.26.0'
+    ],
+    packages=[package for package in find_packages(
+    ) if package.startswith("fancy_gym")],
+    package_data={
+        "fancy_gym": find_package_data(extensions_to_include=["*.stl", "*.xml"])
+    },
+    python_requires=">=3.7",
+    url='https://github.com/ALRhub/fancy_gym/',
+    license='MIT license',
+    author_email='',
+    description='Fancy Gym: Unifying interface for various RL benchmarks with support for Black Box approaches.'
+)