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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 _py_ctype(parameter):
 """Returns the ctypes type name for the specified fortran parameter. """

    ctype = parameter.ctype
    if ctype is None:
        raise ValueError("Can't bind ctypes py_parameter for parameter"
                         " {}".format(parameter.definition()))
    return ctype.lower()