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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _lint():
 """Run lint and return an exit code."""

    # Flake8 doesn't have an easy way to run checks using a Python function, so
    # just fork off another process to do it.

    # Python 3 compat:
    # - The result of subprocess call outputs are byte strings, meaning we need
    #   to pass a byte string to endswith.
    project_python_files = [filename for filename in get_project_files()
                            if filename.endswith(b'.py')]
    retcode = subprocess.call(
        ['flake8', '--max-complexity=10'] + project_python_files)
    if retcode == 0:
        print_success_message('No style errors')
    return retcode