def METHOD_NAME(self, port_num, lpmode):
    # Check for invalid port_num
    if port_num < self.qsfp_port_start or port_num > self.qsfp_port_end:
        return False
    try:
        eeprom = None
        if not self.get_presence(port_num):
            return False  # Port is not present, unable to set the eeprom
        # Fill in write buffer
        regval = 0x3 if lpmode else 0x1  # 0x3:Low Power Mode, 0x1:High Power Mode
        buffer = create_string_buffer(1)
        buffer[0] = chr(regval)
        # Write to eeprom
        eeprom = open(self.port_to_eeprom_mapping[port_num], "r+b")
        eeprom.seek(93)
        eeprom.write(buffer[0])
        return True
    except IOError as e:
        print("Error: unable to open file: %s" % str(e))
        return False
    finally:
        if eeprom is not None:
            eeprom.close()
            time.sleep(0.01)