code: def convert_ints_to_bytes(in_ints, num):
      
      out_bytes= b""
      for val in in_ints:
          out_bytes+=struct.pack(mmtf.utils.constants.NUM_DICT[num], val)
      return out_bytes
docs: Convert an integer array into a byte arrays. The number of bytes forming an integer
      is defined by num
  
      :param in_ints: the input integers
      :param num: the number of bytes per int
      :return the integer array