Standard Python setup.py installer for the PYSWMM library

 Below is an extended summary of the code, highlighting its purpose, key functionalities, and structure:

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Overview and Purpose
The script is a standard Python setup.py installer for the pyswmm library, which serves as a Python wrapper for the SWMM5 (Storm Water Management Model) API. It leverages the setuptools library to package and distribute pyswmm by defining metadata, dependencies, and additional configurations. This allows developers and users to install the library easily using tools like pip or other Python package managers.

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Key Functions and Features

1. Version Extraction (get_version)

   • The get_version function dynamically reads the version from pyswmm/__init__.py.
   • It uses the ast.literal_eval function to parse the VERSION_INFO tuple found in the file.
   • This approach ensures that the package version stays consistent and centralized, avoiding manual, error-prone duplication of version strings.

2. Long Description Retrieval (get_description)

   • The get_description function reads the README.md file to fetch the long description of the package.
   • By specifying long_description_content_type='text/markdown', it tells PyPI and other package repositories to interpret the long description as Markdown for a more visually appealing presentation.

3. Dependencies and Requirements

   • The REQUIREMENTS list includes packages (swmm-toolkit, julian, aenum, and packaging) necessary for running pyswmm.
   • The extras_require dictionary defines additional dependencies pinned to specific SWMM toolkit versions. Each key corresponds to a SWMM5 version, while its value references the required toolkit version. This makes it straightforward for users to install a configuration matching their preferred SWMM version.

4. Metadata and Package Information

   • The setup function includes a variety of metadata such as:
     • Name (pyswmm)
     • Description (“Python Wrapper for SWMM5 API”)
     • URL (“https://www.pyswmm.org”)
     • Author (Bryant E. McDonnell)
     • Licensing information (“BSD2 License”)
     • Key topics and keywords (hydraulic and hydrology modeling, SWMM, etc.)
   • This metadata ensures proper categorization and discoverability on package repositories.

5. Supported Python Versions

   • The classifiers list explicitly states support for Python versions 3.7 through 3.12.
   • It also designates the package’s maturity as “Development Status :: 5 - Production/Stable,” indicating it is ready for widespread use.

6. Included Files and Data

   • By specifying packages=find_packages(exclude=['contrib', 'docs']), the script automatically includes all sub-packages within the pyswmm directory (except directories like contrib and docs).
   • The package_data dictionary includes additional files such as LICENSE.txt, AUTHORS, and test inputs (.inp files), ensuring they are packaged alongside the code.

7. Installation Command

   • After defining all setup parameters, the script culminates in a call to the setup function, which orchestrates the build, distribution, and installation process.

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Conclusion
Overall, this setup.py script is a classic example of Python packaging. It consolidates version management, documentation, and dependency handling into a single file, ensuring that pyswmm can be seamlessly installed and that different SWMM versions are supported through an organized extras_require mechanism. This well-structured setup process enables developers and practitioners alike to integrate pyswmm into their hydraulic and hydrological modeling workflows with minimal friction.