call a variable from one function to another ...

[evilcode1]

hello all ...
i need to call this variable ( filename )from function qassam() inside another fileex() ..
this is my code :

import os 
def qassam():
        filename = "/root/Downloads/scapy.txt"
        #return filename


def fileex():
    filename = qassam
    if os.path.isfile(filename):
        print("is there")
    else:
        print("else ... ")
        
fileex()

error :

Error:
Traceback (most recent call last):
  File "/tmp/ArpScanner/arp.py", line 15, in <module>
    fileex()
  File "/tmp/ArpScanner/arp.py", line 10, in fileex
    if os.path.isfile(filename):
  File "/usr/lib/python2.7/genericpath.py", line 37, in isfile
    st = os.stat(path)
TypeError: coercing to Unicode: need string or buffer, function found