(defn add-phone
  "Add a phone number to a given service. There are a few steps we have to take:
    - Validate the service name and token
...

(defn- index-maze 
  ([maze] (index-maze maze  0 0 {}))
...

(define (compose . fns)
  (define (make-chain fn chain)
...

(define (remove-subnodes n L)
  (cond ((null? L) `())
	((= n (car L)) L)
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#!/usr/bin/guile \
-e main -s
...

;; Turns a flat-list into a list of n-sized lists
;; Examples:
;;   (group-by '(1 2 3 4) 2) => ((1 2) (3 4))
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; 5*O(n)
  (defun next-lex (a)
    (let* ((r (reverse a))
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(defun transpose (m)
       (cond
        ((null (car m)) nil)
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(defun header-encode (string)
  (if (find-if (lambda (c) (> (char-code c) 127)) string)
...