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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 find(self, query):
 """Finds the first cell matching the query. :param query: A literal string to match or compiled regular expression. :type query: str, :py:class:`re.RegexObject` """

        try:
            return self._finder(finditem, query)
        except StopIteration:
            raise CellNotFound(query)