Red-Blue-Purple Gradient

import math
RedBluePurpleList = ('B300B3','9E00B3','8600B3','6E00B3','4800B3','2400B3','4800B3','6E00B3','8600B3','9E00B3','B300B3','B300A7','B30086','B3006E','B3004A','B3002A','B30012','B30000','CC0000','E80000','FF0000')
def RedBluePurple(text):
    x = 18
    leng = len(text)
    output = ''
    if leng < 18:
        for i in range(0, leng):
            output += '<c=#%s>' % RedBluePurpleList[i]
        for i in range(0, leng):
            output += text[i] + '</c>'
    else:
        output += '<c=#'
        output += '><c=#'.join(RedBluePurpleList)
        output += '>'
        size = int(math.ceil(leng / 18.0))
        for i in range(1, 19):
            output += text[(i-1)*size:i*size] + '</c>'
    return output
RedBluePurple.command="RedBluePurple"