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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 exists_uda(self, name, database=None):
 """ Checks if a given UDAF exists within a specified database Parameters name : string, UDAF name database : string, database name Returns ------- if_exists : boolean """

        return len(self.list_udas(database=database, like=name)) > 0