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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 ensure_compliance(self):
 """Ensure that the all registered files comply to registered criteria. """

        for p in self.paths:
            if os.path.exists(p):
                if self.is_compliant(p):
                    continue

                log('File %s is not in compliance.' % p, level=INFO)
            else:
                if not self.always_comply:
                    log("Non-existent path '%s' - skipping compliance check"
                        % (p), level=INFO)
                    continue

            if self._take_action():
                log("Applying compliance criteria to '%s'" % (p), level=INFO)
                self.comply(p)