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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def remove_rules(self, doc):
 """Remove a grammar rules from _self.rules_, _self.rule2func_, and _self.rule2name_ """

        # remove blanks lines and comment lines, e.g. lines starting with "#"
        doc = os.linesep.join([s for s in doc.splitlines() if s and not re.match("^\s*#", s)])

        rules = doc.split()
        index = []
        for i in range(len(rules)):
            if rules[i] == '::=':
                index.append(i-1)
        index.append(len(rules))
        for i in range(len(index)-1):
            lhs = rules[index[i]]
            rhs = rules[index[i]+2:index[i+1]]
            rule = (lhs, tuple(rhs))

            if lhs not in self.rules:
                return

            if rule in self.rules[lhs]:
                self.rules[lhs].remove(rule)
                del self.rule2func[rule]
                del self.rule2name[rule]
                self.ruleschanged = True

                # If we are profiling, remove this rule from that as well
                if self.profile_info is not None and len(rule[1]) > 0:
                    rule_str = self.reduce_string(rule)
                    if rule_str and rule_str in self.profile_info:
                        del self.profile_info[rule_str]
                        pass
                    pass
                pass

        return