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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 write_sources_file():
 """Write a sources.yaml file to current working dir."""

    file_content = (
        'schemes: '
        'https://github.com/chriskempson/base16-schemes-source.git\n'
        'templates: '
        'https://github.com/chriskempson/base16-templates-source.git'
    )
    file_path = rel_to_cwd('sources.yaml')
    with open(file_path, 'w') as file_:
        file_.write(file_content)