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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 _serialize_argument(rargname, value, varprops):
 """Serialize an MRS argument into the SimpleMRS format."""

    _argument = '{rargname}: {value}{props}'
    if rargname == CONSTARG_ROLE:
        value = '"{}"'.format(value)
    props = ''
    if value in varprops:
        props = ' [ {} ]'.format(
            ' '.join(
                [var_sort(value)] +
                list(map('{0[0]}: {0[1]}'.format,
                         [(k.upper(), v) for k, v in varprops[value]]))
            )
        )
        del varprops[value]  # only print props once
    return _argument.format(
        rargname=rargname,
        value=str(value),
        props=props
    )