new_contents: import unittest
  from mppsolar import mppcommand
  
  
  class test_mppcommand(unittest.TestCase):
      def test_crc(self):
          """ Test crc function generates correct crc """
          self.assertListEqual(mppcommand.crc('QPIGS'), [183, 169])
          self.assertListEqual(mppcommand.crc('QPIRI'), [248, 84])
          self.assertListEqual(mppcommand.crc('PSDV56.4'), [249, 224])
          self.assertListEqual(mppcommand.crc('186'), [41, 60])
          self.assertListEqual(mppcommand.crc('196'), [27, 14])
  
subject: Create test_mppcommand.py