code: def is_seq(arg):
      '''
      is_seq(arg) yields True if arg is a sequential collection otherwise False; i.e., it must be a
        list, tuple, persistent vector, persistent list, or numpy array.
      
      Note that strings are not considered sequences.
      '''
      return isinstance(arg, (list_type, tuple_type, pyr.PVector, pyr.PList)) or is_nparray(argf is_seq(arg):
      '''
      is_seq(arg) yields True if arg is a sequential collection otherwise False; i.e., it must be a
        list, tuple, persistent vector, persistent list, or numpy array.
      
      Note that strings are not considered sequences.
      '''
      return isinstance(arg, (list_type, tuple_type, pyr.PVector, pyr.PList)) or is_nparray(arg)
docs: is_seq(arg) yields True if arg is a sequential collection otherwise False; i.e., it must be a
        list, tuple, persistent vector, persistent list, or numpy array.
      
      Note that strings are not considered sequences.