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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 imageinfo(self, files):
 """ Returns imageinfo query string """

        files = '|'.join([safequote(x) for x in files])

        self.set_status('imageinfo', files)

        return self.IMAGEINFO.substitute(
            WIKI=self.uri,
            ENDPOINT=self.endpoint,
            FILES=files)