def _validate_dtype(self, dtype):
    ' validate the passed dtype '
    if (dtype is not None):
        dtype = pandas_dtype(dtype)
        if (dtype.kind == 'V'):
            raise NotImplementedError('compound dtypes are not implemented in the {0} constructor'.format(self.__class__.__name__))
    return dtype
validate the passed dtype
def _validate_dtype(self, dtype):
    '  '
    if (dtype is not None):
        dtype = pandas_dtype(dtype)
        if (dtype.kind == 'V'):
            raise NotImplementedError('compound dtypes are not implemented in the {0} constructor'.format(self.__class__.__name__))
    return dtype