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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 validate(self, sources):
 """Validate the format of sources """

        if not isinstance(sources, Root):
            raise Exception("Source object expected")

        parameters = self.get_uri_with_missing_parameters(sources)
        for parameter in parameters:
            logging.getLogger().warn('Missing parameter "%s" in uri of method "%s" in versions "%s"' % (parameter["name"], parameter["method"], parameter["version"]))