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):
        """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.
        """
        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")  # --DEPARTURE--
            # To match the published algorithm, replace this phrase with
            #   if self.ends("abli"):      self.r("able")
            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":  # --DEPARTURE--
            if self.ends("logi"):
                self.r("log")