def _quote_arg(arg):
    """
    Quote the argument for safe use in a shell command line.
    """
    # If there is a quote in the string, assume relevants parts of the
    # string are already quoted (e.g. '-I"C:\\Program Files\\..."')
    if '"' not in arg and ' ' in arg:
        return '"%s"' % arg
    return arg

    Quote the argument for safe use in a shell command line.
    
numba/pycc/platform.py