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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 build_readme(base_path=None):
 """Call the conversion routine on README.md to generate README.rst. Why do all this? Because pypi requires reStructuredText, but markdown is friendlier to work with and is nicer for GitHub."""

    if base_path:
        path = os.path.join(base_path, 'README.md')
    else:
        path = 'README.md'
    convert_md_to_rst(path)
    print("Successfully converted README.md to README.rst")