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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 execute(self, conn, migration_url="", migration_input="", create_by="", migration_request_id="", transaction=False):
 """ Lists the oldest request queued """

        binds = {}
	result = self.dbi.processData(self.sql, binds, conn, transaction)
        result = self.formatDict(result)
	if len(result) == 0 :
	    return []
	if result[0]["migration_request_id"] in ('', None) :
	    return []
        return result