#!/usr/bin/python

# P2PU - Python Programming 101 - Chapter 9 - Working with Files
# Python for Informatics - Chapter 7 - Files
# Exercise 7.3

print '\n# Exercise 7.3\n'
fname =  raw_input('Enter a file name: ')
if fname == 'na na boo boo':
    print '*****************************************************'
    print "***  NA NA BOO BOO TO YOU - You have been punk'd  ***"
    print '*****************************************************'
    exit()
try:
    ffile = open(fname)
except:
    print 'File', fname, 'cannot be opened!'
    exit()
count = 0
for line in ffile:
    if line.find('Subject:') != -1:
      count += 1
print 'There were %d subject lines in %s' % (count, fname)