title: updated dictionary fails to recognize the newly added key when program is executed again
body: <p>I am creating a program which will give the password for any account which is already in the dictionary and if the account is not there,it will ask the user to input the password so that it can save for future use.</p>
  
  <p>Though the program updates the dictionary(last print in the  else proves that), but when I again run the program, it doesn't recognize the account which i just added.    </p>
  
  <pre><code>password = {
      'a': 'password of a',
      'b': 'password of b',
      'c': 'password of c'
  }
  
  inp = input("Enter the username ")
  
  if inp in password:
      print("your password is ",password[inp])
  
  else:
     print("your account is not present\n")
     new_password = input("Enter the password for ")
     password.update({inp : new_password})
     print("Hopefully the list is updated ",password)
  </code></pre>
  
  <p>for ex. if my inp=d, it will tell me that account is not there and then ask for the input,it shows the dictionary is updated </p>
  
  <pre><code>{'a': 'a ka password', 'b': 'b ka password', 'c': 'c ka password', 'd': 'password of d'}
  </code></pre>
  
  <p>but next time when i run the program it fails to recognize .</p>
  
  <pre><code>Enter the username d
  your account is not present
  </code></pre>