9.5

# #!/usr/bin/python
#
# By dvdjaco
# Exercise 9.5
#

f = raw_input('Enter a file name: ')

try:
    fhand = open(f)
except IOError, err :
        print "Error opening file", f
        print "Error was:", err
d = dict()

# build a dictionary with all domain names and count the number of messages
# sent from each one
for line in fhand:
    words = line.split()
    if len(words) == 0 or words[0] != 'From' or words[1].find('@') == -1: continue
    address = words[1]
    domain = address[address.find('@') + 1:]
    d[domain] = d.get(domain,0) + 1

print d