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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 git_ls_files(*cmd_args):
 """Run ``git ls-files`` in the top-level project directory. Arguments go directly to execution call. :return: set of file names :rtype: :class:`set` """

    cmd = ['git', 'ls-files']
    cmd.extend(cmd_args)
    return set(subprocess.check_output(cmd).splitlines())