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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 loader_for_type(self, ctype):
 """ Gets a function ref to deserialize content for a certain mimetype. """

        for loadee, mimes in Mimer.TYPES.iteritems():
            for mime in mimes:
                if ctype.startswith(mime):
                    return loadee