def fromtostep(f, t, step):
    """ Return a list containing all the numbers from (f) to (t),
    inclusive, in steps of (step).
    @param f [number]
    @param t [number]
    @param step [number]
    @return [list]
    """
    result = []
    if step == 0: return result
    if step<0:
        direction = -1
    else:
        direction = 1
    value = f
    while value*direction <= t*direction:
        result.append(value)
        value += step
    return result