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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 find_customer(cls, session, mailbox, customer):
 """Return conversations for a specific customer in a mailbox. Args: session (requests.sessions.Session):
 Authenticated session. mailbox (helpscout.models.Mailbox):
 Mailbox to search. customer (helpscout.models.Customer):
 Customer to search for. Returns: RequestPaginator(output_type=helpscout.models.Conversation):
 Conversations iterator. """

        return cls(
            '/mailboxes/%d/customers/%s/conversations.json' % (
                mailbox.id, customer.id,
            ),
            session=session,
        )