docs: def _is_binary_stl(data):
      """
      Determine if this is a binary file through unpacking the first value after the 80th character
      and testing whether this value is greater than zero.  This indicates the number of facets in the file.
      Could possibly extend this to check that the remaining number of bytes is divisible by 50.
      """
      is_bin = False
      start_byte = 0
      end_byte = 80
      _ = data[start_byte:end_byte] # header data
      start_byte = end_byte
      end_byte += 4
      facet_count = struct.unpack('I', data[start_byte:end_byte])[0]
      if facet_count > 0:
          is_bin = True
  
      return is_bin