# L-14 MCS 260 Fri 12 Feb 2010 : global variables
#
# illustration of a global variable
#
v = 2007

def update (formalv):
   "shows value of formal v\
    and prompts for new v"
   print 'v = ', formalv
   new_v = input('Give new value : ')
   return new_v

while True:
   v = update(v) # do not forget ()
   ans = raw_input('continue ? (y/n) ')
   if ans != 'y': break