How to test if a file is a symbolic link?

[Peng Yu]

'symbolic_link' is a symbolic link in the current directory. I run
'python main.py', but it does not return me anything. I want to check
if a file is a symbolic link. I'm wondering what is the correct way to
do so?

$cat main.py
import stat
import os

st = os.stat('symbolic_link')
if stat.S_ISLNK(st.st_mode):
  print "Hello"