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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 getClient(self):
 """Retrieves the Client for which the current Batch is attached to Tries to retrieve the Client from the Schema property, but if not found, searches for linked ARs and retrieve the Client from the first one. If the Batch has no client, returns None. """

        client = self.Schema().getField('Client').get(self)
        if client:
            return client
        client = self.aq_parent
        if IClient.providedBy(client):
            return client