Python: check if an object is a sequence

Question

In python is there an easy way to tell if something is not a sequence? I tried to just do: if x is not sequence but python did not like that

Answer 1

For the sake of completeness. There is a utility is_sequence in numpy library ("The fundamental package for scientific computing with Python").

>>> from numpy.distutils.misc_util import is_sequence
>>> is_sequence((2,3,4))
True
>>> is_sequence(45.9)
False

But it accepts sets as sequences and rejects strings

>>> is_sequence(set((1,2)))
True
>>> is_sequence("abc")
False

The code looks a bit like @adrian 's (See numpy git code), which is kind of shaky.

def is_sequence(seq):
    if is_string(seq):
        return False
    try:
        len(seq)
    except Exception:
        return False
    return True