'Write the given text to the stream in the given color.
@param text: Text to be written to the stream.
@param color: A string label for a color. e.g. \'red\', \'white\'.'

def write(self, text, color):

    color = self._colors[color]
    self.stream.write(('\x1b[%s;1m%s\x1b[0m' % (color, text)))
