The following code is displaying that the user id doesn’t exist in the binary file although the file consist of same data.Can someone tell me the error in the code.

import pickle, os, time from Tkinter import *  class SignUp:     def __init__(self):         self.username=None         self.password=None         self.Name=None     def getinfo(self):         self.username=raw_input('Username:   ')         self.password=raw_input('Password:    ')         self.Name=raw_input('Enter Name:    ')  def Users():     global c2      c2=SignUp()     #print     f=open('namepassword.dat','rb+')     flag = 0     while True:         try:             while True:                 c2=pickle.load(f)                 if not c2:                     break                 else:                     if c2.username <> user or c2.password <> PASS:                         continue                     else:                         flag=1                         print 'Login Ho gaya re Baba'                          break         except EOFError:             pass         if flag==0:             print "User id does not exist"             break         f.close()  def main():     global root     root=Tk()     photo=PhotoImage(file="Capture.gif")     w=Label(root,image=photo)     w.grid(row=0,columnspan=10)     v=Label(root,text="USERNAME",fg="Red")     v.config(font = "Times")     v.grid(row=1,column=4)     global user     user=Entry(root,bd=4)     user.grid(row=2,column=4)     a=Label(root,text="PASSWORD",fg="Red")     a.config(font="Times")     a.grid(row=4,column=4)     global PASS     PASS=Entry(root,bd=4,show="*")     PASS.grid(row=5,column=4)     k=Button(root,text="Log In",command=Users)     k.grid(row=6,column=4)     a=Label(root,text="OR")     a.grid(row=7,column=4)     s=Label(root,text="Sign Up",command=None)     s.grid(row=8,column=4)     root.mainloop() main()