'step2() maps double suffices to single ones.
so -ization ( = -ize plus -ation) maps to -ize etc. note that the
string before the suffix must give m() > 0.'

def step2(self):

    if (self.b[(self.k - 1)] == 'a'):
        if self.ends('ational'):
            self.r('ate')
        elif self.ends('tional'):
            self.r('tion')
    elif (self.b[(self.k - 1)] == 'c'):
        if self.ends('enci'):
            self.r('ence')
        elif self.ends('anci'):
            self.r('ance')
    elif (self.b[(self.k - 1)] == 'e'):
        if self.ends('izer'):
            self.r('ize')
    elif (self.b[(self.k - 1)] == 'l'):
        if self.ends('bli'):
            self.r('ble')
        elif self.ends('alli'):
            self.r('al')
        elif self.ends('entli'):
            self.r('ent')
        elif self.ends('eli'):
            self.r('e')
        elif self.ends('ousli'):
            self.r('ous')
    elif (self.b[(self.k - 1)] == 'o'):
        if self.ends('ization'):
            self.r('ize')
        elif self.ends('ation'):
            self.r('ate')
        elif self.ends('ator'):
            self.r('ate')
    elif (self.b[(self.k - 1)] == 's'):
        if self.ends('alism'):
            self.r('al')
        elif self.ends('iveness'):
            self.r('ive')
        elif self.ends('fulness'):
            self.r('ful')
        elif self.ends('ousness'):
            self.r('ous')
    elif (self.b[(self.k - 1)] == 't'):
        if self.ends('aliti'):
            self.r('al')
        elif self.ends('iviti'):
            self.r('ive')
        elif self.ends('biliti'):
            self.r('ble')
    elif (self.b[(self.k - 1)] == 'g'):
        if self.ends('logi'):
            self.r('log')
