def sum_items_at_even_indices(sequence):
    """
    What comes in:
      -- A sequence of numbers.
    What goes out:
      Returns the sum of the numbers in the list that:
        -- are at EVEN INDICES.
    Side effects:   None.
    Examples:
      sum_items_at_even_indices([3, 10, 6, 5, 5, 10])
        returns 3 + 6 + 5, which is 14

     sum_items_at_even_indices([5.5, 10, 3, 2, 10, 0, 1])
        returns 5.5 + 3 + 10 + 1, which is 19.5

    Type hints:
      :type sequence: list or tuple (of numbers)
    """
    # ------------------------------------------------------------------
    # EXAMPLE 3.  Iterates through and sums the items in a list
    #   of numbers that are at even INDICES.
    #
    #   Constrast this example with the previous example.
    # ------------------------------------------------------------------
    total = 0
    for k in range(0, len(sequence), 2):
        total = total + sequence[k]

    return total

    # Here is a ** BAD alternative ** that computes the right result
    # but takes twice as long to do so as needed.
    total = 0
    for k in range(len(sequence)):  # This is a BAD solution
        if k % 2 == 0:
            total = total + sequence[k]

    return total