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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 parse_rule(cls, txt):
 """Parse a rule from a string. See rezconfig.package_filter for an overview of valid strings. Args: txt (str):
 String to parse. Returns: `Rule` instance. """

        types = {"glob": GlobRule,
                 "regex": RegexRule,
                 "range": RangeRule,
                 "before": TimestampRule,
                 "after": TimestampRule}

        # parse form 'x(y)' into x, y
        label, txt = Rule._parse_label(txt)
        if label is None:
            if '*' in txt:
                label = "glob"
            else:
                label = "range"
        elif label not in types:
            raise ConfigurationError(
                "'%s' is not a valid package filter type" % label)

        rule_cls = types[label]
        txt_ = "%s(%s)" % (label, txt)

        try:
            rule = rule_cls._parse(txt_)
        except Exception as e:
            raise ConfigurationError("Error parsing package filter '%s': %s: %s"
                                     % (txt_, e.__class__.__name__, str(e)))
        return rule