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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 contains_element(self, element):
 """Determines if an element is contained in the priority queue." :returns: bool -- true iff element is in the priority queue. """

        return (element in self.element_finder) and \
            (self.element_finder[element][1] != self.INVALID)