code: def signature(array):
      
      length = len(array)
      index = _NUM_SIGNATURE_BYTES if length > _NUM_SIGNATURE_BYTES else length
  
      return array[:index]
docs: Returns the first 262 bytes of the given bytearray
      as part of the file header signature.
  
      Args:
          array: bytearray to extract the header signature.
  
      Returns:
          First 262 bytes of the file content as bytearray type.