something for a friend

#!/usr/bin/python                                        
import os                                                
import sys                                               
                                                         
def main():                                              
    tree(sys.argv[1] if len(sys.argv)>1 else os.getcwd())
                                                         
def tree(path):
    map(lambda x: walk(*x), os.walk(path))                                      
                                                         
def walk(root, dirs, files):                             
    for fn in files:                                     
        if fn[-4:] == '.xml':                             
            print_if_whited("/".join([root, fn]))        
                                                         
def print_if_whited(fn):                                 
    with open(fn, 'r') as fd:                            
        if fd.readline()[0].isspace():                   
            for line in fd:                              
                pass                                     
            if line[len(line)-1].isspace():              
                print fn                                 
                                                         
if __name__ == '__main__':                               
    main()