code: def decodeGsm7(encodedText):
      
      result = []
      if type(encodedText) == str:
          encodedText = rawStrToByteArray(encodedText) #bytearray(encodedText)
      iterEncoded = iter(encodedText)
      for b in iterEncoded:
          if b == 0x1B: # ESC - switch to extended table
              c = chr(next(iterEncoded))
              for char, value in dictItemsIter(GSM7_EXTENDED):
                  if c == value:
                      result.append(char)
                      break
          else:
              result.append(GSM7_BASIC[b])
      return ''.join(result)
docs: GSM-7 text decoding algorithm
      
      Decodes the specified GSM-7-encoded string into a plaintext string.
      
      :param encodedText: the text string to encode
      :type encodedText: bytearray or str
      
      :return: A string containing the decoded text
      :rtype: str