Use distutils to create a static library (for external usage)

setup.py

from distutils.ccompiler import new_compiler 
from sysconfig import get_paths 
import os

project_name = "slimey_project"
source = ['source1.c']
include_dirs = ['include']
build_dir = os.path.join(os.path.dirname(__file__), 'build')

class StaticLib(Command): 
    description = 'build static lib' 
    user_options = [] # do not remove, needs to be stubbed out! 
    python_info = get_paths() 

    def initialize_options(self):
        pass

    def finalize_options(self):
        pass

    def run(self):
        # Create compiler with default options
        c = new_compiler()

        # Optionally add include directories etc.
        for d in include_dirs:
            c.add_include_dir(d)

        c.add_include_dir(self.python_info['include'])
        # Compile into .o files
        objects = c.compile(sources)

        # Create static or shared library
        c.create_static_lib(objects, project_name, output_dir=build_dir)

How should this actually be invoked? IE how does this fit into an existing setup.py?