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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 spi_ss_polarity(self, polarity):
 """Change the ouput polarity on the SS line. Please note, that this only affects the master functions. """

        ret = api.py_aa_spi_master_ss_polarity(self.handle, polarity)
        _raise_error_if_negative(ret)