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:
"""
(M) "LICENSED MATERIALS" means the Licensed Software and Documentation and includes Maintenance Releases and Enable Codes which Changepoint may from time to time provide to Customer hereunder. (N) "LICENSED SOFTWARE" means the Components of the CHANGEPOINT Software in object code format licensed to Customer hereunder and described in Appendix A and such additional Components of the CHANGEPOINT Software which Customer and Changepoint hereinafter agree shall be added to Appendix A. (O) "MAINTENANCE" has the meaning given to it in Section 4.2. (P) "MAINTENANCE FEES" has the meaning given to it in Section 4.2. (Q) "MAINTENANCE RELEASE" means new versions and releases of the Licensed Software which Changepoint makes generally available to its customers who have contracted with it to receive Maintenance Service for the Licensed Software. (R) "MAINTENANCE SERVICES" means the services described in Section 7.2. (S) "SOFTWARE LICENSES" means the utilization licenses and associated restrictions with respect to the Licensed Software granted to Customer hereunder which are set forth in Appendix A. (T) "WARRANTY PERIOD" means the period as set out in Appendix A. (U) "WARRANTY SUPPORT" means the warranty support set forth in Section 6.1(a). ARTICLE 2 - LICENSE 2.1 LICENSE (a) Subject to the provisions of this Agreement including the provisions of Article 8, Changepoint hereby grants to Customer and Customer hereby accepts from Changepoint the perpetual, personal, non-transferable and non-exclusive Software Licenses to use the Licensed Software for Customer's internal business purposes. Customer may also make a reasonable number of back-up copies, but not to exceed two (2) copies, of the Licensed Software for use as part of Customer's disaster recovery plan. (b) The Licensed Materials may be used only as set out in this Agreement and Customer agrees not to make any copies (whether in electronic or any other form) or use thereof other than as expressly permitted herein or by Changepoint in writing in advance, even if it is technically feasible to do so. Without limiting the generality of the foregoing, Customer agrees to use the Licensed Software only to the extent authorized by the Software Licenses. (c) Customer's License to use the Licensed Materials shall commence on the Effective Date. 2.2 DOCUMENTATION 30 The Documentation may be used by Customer at Customer sites for the purpose of assisting Customer in using the Licensed Software for the internal business purposes of Customer. Changepoint agrees to deliver one copy of the Documentation to Customer in either printed or electronic form. Documentation provided in machine readable form may be printed and used solely for the internal business purposes of Customer. No other reproduction or use of the Documentation is permitted. 2.3 THIRD PARTY USERS For the purpose of operating Customer's business, the parties intend that certain unrelated third parties with whom Customer has a business relationship such as a supplier or customer and the employees of such third person (hereunder "Business Third Parties"), will have limited right to use certain Components of the Licensed Software solely for the purpose of providing services to Customer. All such persons must execute an agreement in writing with Customer to maintain the Confidential Information in confidence and to use the Licensed Materials only as permitted. Customer agrees to strictly enforce the provisions of such non-disclosure agreements set forth in this Section 2.3 and all other provisions of this Agreement as applicable to any and all uses of the Licensed Materials. ARTICLE 3 - DELIVERY AND INSTALLATION 3.1 DELIVERY OF LICENSED MATERIALS Changepoint agrees to deliver to Customer one (1) copy of the most current release and version of the Licensed Materials. The Documentation will be provided solely in the English language. 3.2 INSTALLATION SERVICES Changepoint agrees to provide the installation services (the "Installation Services") described in Appendix A. 3.3 ENABLE CODES To enable Customer to install the Licensed Software, Changepoint will provide Customer with information or data which are intended to enable the Licensed Software to be used ( the "Enable Codes"). The Enable Codes are designed to enable Customer to use the Licensed Software in accordance with the number of Software Licenses acquired hereunder. Customer acknowledges and agrees that additional Enable Codes will need to be obtained from Changepoint if Customer acquires one or more additional Software Licenses from Changepoint. Customer agrees not to, and shall cause all users not to, modify, adapt or create derivative works of any Enable Codes provided, develop or have developed any Enable Codes, or use any Enable Codes other than those provided by Changepoint. ARTICLE 4 - PRICE AND PAYMENT TERMS 4.1 LICENSE
"""

Extract the exact clause related to "Irrevocable Or Perpetual License" from the excerpt above.

assistant: Subject to the provisions of this Agreement including the provisions of Article 8, Changepoint hereby grants to Customer and Customer hereby accepts from Changepoint the perpetual, personal, non-transferable and non-exclusive Software Licenses to use the Licensed Software for Customer's internal business purposes.