python regex not matching

I want to check that only a numbers exists in a string

Cast to int

a="22tim22"
if type(a)==int:
    print("ok")

Regex

import re
a="22tim22"
b=re.findall('([^0-9]),a)
if len(b)==0:
    print("Bad - This has non numbers in it")
else:
    print("Number no bad chars")