Joint accounts
    Consider the bank account objects created by 
    make-account
    , with the password modification described in exercise 
    3.3
    . Suppose that our banking system requires the ability to make joint accounts. Define a procedure 
    make-joint
     that accomplishes this. 
    Make-joint
     should take three arguments. The first is a password-protected account. The second argument must match the password with which the account was defined in order for the 
    make-joint
     operation to proceed. The third argument is a new password. 
    Make-joint
     is to create an additional access to the original account using the new password. For example, if 
    peter-acc
     is a bank account with password 
    open-sesame
    , then
(define paul-acc
    (make-joint peter-acc 'open-sesame 'rosebud))
    will allow one to make transactions on 
    peter-acc
     using the name 
    paul-acc
     and the password 
    rosebud
    . You may wish to modify your solution to exercise 
    3.3
     to accommodate this new feature.