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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 is_public(self):
 """Returns True if the public-read ACL is set for the Key."""

        for grant in self._boto_object.Acl().grants:
            if 'AllUsers' in grant['Grantee'].get('URI', ''):
                if grant['Permission'] == 'READ':
                    return True

        return False