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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_bitrate(self):
 """SPI bitrate in kHz. Not every bitrate is supported by the host adapter. Therefore, the actual bitrate may be less than the value which is set. The slowest bitrate supported is 125kHz. Any smaller value will be rounded up to 125kHz. The power-on default value is 1000 kHz. """

        ret = api.py_aa_spi_bitrate(self.handle, 0)
        _raise_error_if_negative(ret)
        return ret