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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 GetMemShares(self):
        '''Retrieves the number of memory shares allocated to the virtual machine.
           For information about how an ESX server uses memory shares to manage
           virtual machine priority, see the vSphere Resource Management Guide.'''
        counter = c_uint()
        ret = vmGuestLib.VMGuestLib_GetMemShares(self.handle.value, byref(counter))
        if ret != VMGUESTLIB_ERROR_SUCCESS: raise VMGuestLibException(ret)
        return counter.value