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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 compliance_uri(self):
 """Compliance URI based on api_version. Value is based on api_version and complicance_level, will be None if either are unset/unrecognized. The assumption here is that the api_version and level are orthogonal, override this method if that isn't true. """

        if (self.api_version == '1.0'):
            uri_pattern = r'http://library.stanford.edu/iiif/image-api/compliance.html#level%d'
        elif (self.api_version == '1.1'):
            uri_pattern = r'http://library.stanford.edu/iiif/image-api/1.1/compliance.html#level%d'
        elif (self.api_version == '2.0' or
              self.api_version == '2.1'):
            uri_pattern = r'http://iiif.io/api/image/2/level%d.json'
        else:
            return
        if (self.compliance_level is None):
            return
        return(uri_pattern % self.compliance_level)