add .gitignore to Enhance Project Cleanliness and Security (#25)

* Add .gitignore to prevent tracking unnecessary files

* Update .gitignore

Following suggestion to not ignore .python-version and to ignore .venv

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Co-authored-by: Jonathan Taylor <jonathan.taylor@stanford.edu>

.gitignore

@@ -0,0 +1,51 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# Jupyter Notebook
+.ipynb_checkpoints/
+*.ipynb_checkpoints/
+*.ipynb_meta
+
+# Python environments
+env/
+venv/
+.venv/
+ENV/
+env.bak/
+venv.bak/
+.spyderproject
+.spyproject
+.ropeproject
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# PyInstaller
+*.manifest
+*.spec
+
+# Operating System
+.DS_Store
+
+# IDEs
+.vscode/
+.idea/