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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 speed_info(self):
 """Retrieves information about supported target interface speeds. Args: self (JLink):
 the ``JLink`` instance Returns: The ``JLinkSpeedInfo`` instance describing the supported target interface speeds. """

        speed_info = structs.JLinkSpeedInfo()
        self._dll.JLINKARM_GetSpeedInfo(ctypes.byref(speed_info))
        return speed_info