system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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shall Wells Fargo Bank, N.A. in its individual capacity be personally liable for the payment of any indebtedness or expenses or be personally liable for the breach or failure of any obligation, representation, warranty or covenant made or undertaken by the Trust under this Confirmation or any other related documents (other than the Master Servicer's express obligations under the Pooling and Servicing Agreement). References in this clause to "a party" shall, in the case of UBS AG and where the context so allows, include references to any affiliate of UBS AG. Account Details for UBS AG: Currency: USD Correspondent Bank: UBS AG, STAMFORD BRANCH Swift Address: UBSWUS33XXX Favour: UBS AG LONDON BRANCH Swift Address: UBSWGB2LXXX Account No: 101-wa-140007-000 Offices (a) The office of UBS AG for the Interest Rate Cap Transaction is London; and The office of Counterparty for the Interest Rate Cap Transaction is: 9062 Annapolis Road Columbia, Maryland 21045 Attn: Client Manager - WFMBS 2006-6 Telephone: 410.884.2000 Fax: 410.715.2380 Contact Names at UBS AG: Payment Inquiries Elisa Doctor Email: &bbsp; DL-USOTCRATES-SETTS@ubs.com Phone: 203.719.1110 Pre Value Payments: Pre Value Payment 203.719.1110 Investigations: Post Value Payments: Post Value Payment 203.719.1110 Investigations: Confirmation Queries: Confirmation Control: 203.719.3373 ISDA Documentation: Credit Risk Management: 212.713.1170 Swift: UBSWGB2L Fax: 203.719.0274 Address: UBS AG 100 Liverpool Street London EC2M 2RH Address for notices or communications to the Counterparty: 9062 Old Annapolis Road Columbia, MD 21045 Attn: Corporate Trust Services - WFMBS 2006-6 Payments to Counterparty: Wells Fargo Bank, NA San Francisco, CA ABA #: 121-000-248 Acct #: 3970771416 Acct Name: SAS Clearing For Further Credit: Interest Rate Cap, Account # 50915701 (For all purposes) Please confirm that the foregoing correctly sets forth the terms and conditions of our agreement by executing a copy of this Confirmation and returning it to us or by sending to us a letter or facsimile substantially similar to this letter, which letter or facsimile sets forth the material terms of the Transaction to which this Confirmation relates and indicates your agreement to those terms or by sending to us a return letter or facsimile in the form attached. This Confirmation may be executed in several counterparts, each of which shall be deemed an original but all of which together shall constitute one and the same instrument. Yours Faithfully For and on Behalf of UBS AG, London Branch By: /s/ Todd Harper By: /s/ Mark J. Evans II Name : Todd Harper Name : Mark J. Evans II Title : Associate Director Title: Director UBS Operations Operations Acknowledged and Agreed by Wells Fargo Bank N.A., not individually, but solely as Master Servicer on behalf of Wells Fargo Mortgage Backed Securities 2006-6 Trust By: /s/ Jennifer L. Richardson Name : Jennifer L. Richardson Title : Assistant Vice President UBS AG London Branch, 1 Finsbury Avenue, London, EC2M 2PP UBS AG is a member of the London Stock Exchange and is regulated in the UK by the Financial Services Authority. Representatives of UBS Limited introduce trades to UBS AG via UBS Limited.
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Extract the exact clause related to "Warranty Duration" from the excerpt above.

assistant: Not found.