(define (make-account balance password)
  (define (withdraw amount)
    (if (>= balance amount)
        (begin (set! balance (- balance amount))
               balance)
        "Insufficient funds"))
  (define (deposit amount)
    (set! balance (+ balance amount))
    balance)
  (define wrong-guesses 0)
  (define (dispatch credential m)
    (define (call-the-cops)
      (display "Calling the cops"))
    (if (eq? credential password)
        (set! wrong-guesses 0)
        (begin
          (set! wrong-guesses (+ wrong-guesses 1))
          (if (> wrong-guesses 7)
              (call-the-cops))
          (error "Incorrect password")))
    (cond ((eq? m 'withdraw) withdraw)
          ((eq? m 'deposit) deposit)
          (else (error "Unknown request -- MAKE-ACCOUNT" m))))
  dispatch)