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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 _ctypes_dtype(parameter):
 """Determines the ISO_C data type to use for describing the specified parameter. """

    ctype = parameter.ctype
    if ctype is None:
        if parameter.kind is not None:
            return "{}({})".format(parameter.dtype, parameter.kind)
        else:
            return parameter.dtype
    else:
        return"{}({})".format(parameter.dtype, ctype)