Try giving sgp4_pure_python its own setup.py

pure_python/setup.py

@@ -0,0 +1,55 @@
+from distutils.core import setup
+
+# Place this `setup.py` at the root of the project to build and
+# distribute a pure-Python version of SGP4.
+
+# Read the package's docstring and "__version__" without importing it.
+path = 'sgp4/__init__.py'
+with open(path, 'rb') as f:
+    text = f.read().decode('utf-8')
+text = text.replace('-*- coding: utf-8 -*-', '')  # for Python 2.7
+
+namespace = {}
+eval(compile(text, path, 'exec'), namespace)
+
+version = namespace['__version__']
+description, long_description = namespace['__doc__'].split('\n', 1)
+
+# Avoid "`long_description` has syntax errors in markup" from extra
+# whitespace that somehow creeps in.
+description = description.strip()
+long_description = """\
+This distribution provides the `sgp4 package <https://pypi.org/project/sgp4/>`_
+for computing Earth satellite positions, but without making any attempt to
+compile and install the accelerated C++ version of the algorithm.  Instead,
+it is implemented in (rather slow) pure Python code.
+"""
+
+setup(
+    name = 'sgp4_pure_python',
+    version = version,
+    description = description,
+    long_description = long_description,
+    long_description_content_type = 'text/x-rst',
+    license = 'MIT',
+    author = 'Brandon Rhodes',
+    author_email = '[email protected]',
+    url = 'https://github.com/brandon-rhodes/python-sgp4',
+    classifiers = [
+        'Development Status :: 5 - Production/Stable',
+        'Intended Audience :: Science/Research',
+        'License :: OSI Approved :: MIT License',
+        'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 2.7',
+        '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 :: Astronomy',
+    ],
+    packages = ['sgp4'],
+    package_data = {'sgp4': ['SGP4-VER.TLE', 'sample*', 'tcppver.out']},
+    provides = ['sgp4'],
+)