code: def _SkipVarint(buffer, pos, end):
    
    # Previously ord(buffer[pos]) raised IndexError when pos is out of range.
    # With this code, ord(b'') raises TypeError.  Both are handled in
    # python_message.py to generate a 'Truncated message' error.
    while ord(buffer[pos:pos+1]) & 0x80:
      pos += 1
    pos += 1
    if pos > end:
      raise _DecodeError('Truncated message.')
    return pos
docs: Skip a varint value.  Returns the new position.