How do I know if a value is eternal in Python?

Question

How can I check in Python if a certain value is eternal?

What determines that a particular type can be eternal?

For example, how to find out this in the case below?

a = 1 
b = 'Uma string'
c = [1, 2, 3]
d = xrange(1, 10)
e = range(1, 10)
f = {"a" : 1}
g = True

Answer 1

I haven’t seen any article or document citing exactly how to do this "great". Meanwhile, the Miku, of Stackoverflow in English, cited some examples.

You can try something like:

1- Assuming the object is always iterable and then capturing the error if it is not, in style Pythonico - EAFP (Easier to Ask Forgiveness than Permission) - "better to ask forgiveness than permission"

try:
    _ = (e for e in my_object)
except TypeError:
    print my_object, 'is not iterable'

Or:

2- Using the module collections

import collections

if isinstance(e, collections.Iterable):
    # e is iterable

Answer 2

Two Pythonic Ways to Check This.

With try-except

try:
    iterator = iter(var)
except TypeError:
    # não iterável
else:
    # iterável

Checking by abstract class

Only works with classes new style - which do not exist in versions smaller than 2.2.

import collections

if isinstance(var, collections.Iterable):
    # iterável
else:
    # não iterável