#!/usr/bin/env ipython
def clamp(val, low, high):
    return min(high, max(low, val))


def rgb2hex(r, g, b, a=None):
    hex_value = "#{:02x}{:02x}{:02x}".format(
        int(r * 255),
        int(g * 255),
        int(b * 255)
    )
    return hex_value