def sum_sequence(sequence):
    """
    What comes in:  A sequence of integers.
    What goes out: Returns the sum of the numbers in the given sequence.
    Side effects: None.
    Examples:
      sum_sequence([8, 13, 7, -5])  returns  23
      sum_sequence([48, -10])       returns  38
      sum_sequence([])              returns  0
    Type hints:
      :type sequence: list or tuple (of integers)
    """
    # -------------------------------------------------------------------------
    # DONE: 3. Implement and test this function.
    #          Tests have been written for you (above).
    #
    # RESTRICTION:
    #    You may NOT use the built-in  sum   function
    #    in IMPLEMENTING this function.
    #      -- The TESTING code above does use   built_ins.sum
    #         as an ORACLE in TESTING this function, however.
    # -------------------------------------------------------------------------
    total = 0
    for k in range(len(sequence)):
        total = total + sequence[k]
    return total