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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 open(self):

 """
 Calls SetupDiGetClassDevs to obtain a handle to an opaque device
 information set that describes the device interfaces supported by all
 the USB collections currently installed in the system. The
 application should specify DIGCF.PRESENT and DIGCF.INTERFACEDEVICE
 in the Flags parameter passed to SetupDiGetClassDevs.
 """

        self.h_info = SetupDiGetClassDevs(byref(self.guid), None, None,
                (DIGCF.PRESENT | DIGCF.DEVICEINTERFACE) )

        return self.h_info