feat: initial skeleton

.flake8

+[flake8]
+select = E,F,W
+max_line_length = 79
+ignore = E402, W503
+exclude =
+  .git,
+  .tox,
+  .eggs,
+  .config,
+  *.egg-info,
+  __pycache__,
+  .pytest_cache,
+  env,

.gitignore

+## Derived Files
+coverage.xml
+
+# Python
+*.py[cod]
+*.egg-info
+.eggs/
+.pytest_cache/
+.tox
+.vscode
+.coverage
+
+# Other
+images_rc.py
+config/ramsis_config_public.yml
+
+## Development Tools
+
+# PyCharm IDE
+.idea/
+
+# Vim
+*.swp
+
+# Sphinx
+doc/manual/_build
+doc/_build
+
+# QT Creator
+*.autosave
+
+# Virtual environment
+venv*
+env/
+env*/
+.env
+.env.test
+
+## OS specific files
+
+# Mac
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+Icon?
+thumbs.db
+Thumbs.db
+
+
+## Config files
+settings.yml
+

pyproject.toml

+[build-system]
+requires = ["setuptools>=75.0.0", "wheel>=0.44.0"]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools.packages.find]
+where = [""]
+include = ["psha.*"]
+
+[project]
+name = "psha"
+version = "0.1.0"
+description = ""
+readme = "README.md"
+authors = [
+    { name = "Ali Gottschall" },
+    { name = "Nicolas Schmid", email = "nicolas.schmid@sed.ethz.ch" },
+]
+license = { file = "LICENSE" }
+
+dependencies = ["geopandas", "ipykernel", "numpy", "pandas"]
+
+requires-python = ">=3.10"
+
+[project.optional-dependencies]
+dev = ["pytest", "isort", "pytest-cov", "tox", "flake8"]
+
+[tool.pytest.ini_options]
+addopts = ["--import-mode=importlib"]
+filterwarnings = ["ignore:divide by zero"]