Dark Rainbow

import math
gradient = ('9400D3', '4B0082', '0000FF', '00FF00', 'FFFF00', 'FF7F00', 'FF0000')
def gradientmadness(text):
         leng = len(text)
         output = ''
         if leng < 7:
             for i in range(0, leng):
                 output += '<c=#%s>' % gradient[i]
             for i in range(0, leng):
                 output += text[i] + '</c>'
         else:
             output += '<c=#'
             output += '><c=#'.join(gradient)
             output += '>'
             size = int(math.ceil(leng / 7.0))
             for i in range(1, 7+1):
                 output += text[(i-1)*size:i*size] + '</c>'
         return output
gradientmadness.command="Rainbow"



^(.*)$
Rainbow(\1)