Python any()

Python built-in module provides method any()  which  returns True if any element of an iterable is true. If not this method would  return False.

syntax :

any(iterable)    ##   iterable could be list, string dict etc

return value:

• True  ##   if any 1 of iterable is True
• False ##   if all are false  or the list is empty  

Examples :

>>> a = [0,0]  ## 0 defaults to False
>>> any(a)
False
>>> a = [1,2]  ## Both are True
>>> any(a)
True
>>> a = []   ## empty list False 
>>> any(a)
False
>>> a = [0,0,0,1]  ## If any element is True
>>> any(a)
True

Using any() with 2 lists :

Suppose We have two lists a and b and we want to check if element in a exists in b. 

So we define function :

def func(a, b):
    for i in a:
       if i in b:
          return True
    return False

This could be easily realised with any() in one line as :

any(i in b for i in a)

For Example:

>>> a = [1,2,3,4]
>>> b = [4,5,6,7]
False
>>> def func(a, b):
        for i in a:
           if i in b:
              return True
 return False
>>> print func(a,b)
True
>>> any(i in b for i in a)
True