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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 match_sequence(self, tokens, item):
 """Matches a sequence."""

        tail = None
        if len(tokens) == 2:
            series_type, matches = tokens
        else:
            series_type, matches, tail = tokens
        self.add_check("_coconut.isinstance(" + item + ", _coconut.abc.Sequence)")
        if tail is None:
            self.add_check("_coconut.len(" + item + ") == " + str(len(matches)))
        else:
            self.add_check("_coconut.len(" + item + ") >= " + str(len(matches)))
            if tail != wildcard:
                if len(matches) > 0:
                    splice = "[" + str(len(matches)) + ":]"
                else:
                    splice = ""
                self.assign_to_series(tail, series_type, item + splice)
        self.match_all_in(matches, item)