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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and expenses incurred by Transporter as the result of any unspent and/or unneutralized acids being present in the Crude Petroleum delivered to Transporter by Shipper. Shipper will be billed for all such extra costs and expenses for shutting down, purging of such unspent acids, and subsequent resuming operation of the Transporter's Gathering System. Transporter shall not be liable to any Shipper for any damage sustained by Shipper(s) as the result of unspent and/or unneutralized acids being received from other Shipper(s). 5.10 In the event that Shipper does not operate the wells from which the Crude Petroleum nominated for shipment is produced or does not operate the treating, measurement, or pumping equipment through which such Crude Petroleum is handled prior to its delivery to Transporter, then Shipper shall designate the party or parties responsible for the operation of such facilities and shall authorize and direct such party or parties to (1) comply with all provisions of this Agreement related to their operations and (2) furnish to Transporter such reasonably requested operational, technical, administrative, and analytical data as Transporter deems necessary to account for volumes being delivered to Transporter and assure safe, lawful, and efficient operations. ARTICLE 6 GRAVITY BANK 6.1 To assure that no shipper will be materially damaged or allowed to benefit by changes in gravity due to the intermixing of petroleum in the Gathering System, Shipper will be required, as a condition of tendering, to participate in a Gravity Bank. The table of gravity differential values per barrel as attached hereto as Exhibit B is incorporated herein and made a part of this Agreement. 8 6.2 Transporter shall administer the Gravity Bank providing adjustments for the value of crudes with different qualities in the manner specified below for both receipt and delivery volumes. Applicable barrels and gravities shall be the net barrels at 60 degrees Fahrenheit (with no deduction for Loss allowance) and the gravities recorded by the Operator at points where it customarily records gravities and quantities. The weighted average gravity differential value per barrel (for two or more gravities of petroleum), as hereinafter referred to, shall be obtained in the following manner: multiply the gravity differential values per barrel (from the attached table as same is from time to time revised) by the number of barrels to which such gravity differential values are applicable and then divide the total of the resultant gravity differential values in dollars and cents by the total of the applicable barrels. 6.3 Adjustments between shippers shall be computed as follows: (i) compute the weighted average gravity differential value per barrel of the barrels received from by each shipper and (ii) compute the weighted average gravity differential value per barrel of the composite common stream for receipts. 6.4 Calculation: (a) If the weighted average gravity differential value per barrel of a shipper as so determined under Section 6.3(i) above shall be greater than the weighted average gravity differential value per barrel of the aforementioned common stream petroleum as determined under Section 6.3(ii), the difference in cents per barrel shall be calculated and shipper shall be credited (receives) an amount calculated by multiplying said difference in gravity differential value per barrel by the applicable barrels. (b) If the weighted average gravity differential value per barrel of a shipper is less than the weighted average gravity differential value per barrel of the aforementioned common stream petroleum, the difference shall be calculated as above outlined and a shipper debited for such difference. (c) A sample calculation is attached as Exhibit C. 6.5 These calculations shall be made for each calendar month and the algebraic sum of the adjustments for the system shall be zero +/- One Dollar. If a shipper shall have a net debit balance in combining the two adjustments made above, the balance shall be remitted to the clearinghouse within fifteen (15) days from receipt of statement of such debit. If Shipper shall have a credit, the clearinghouse shall remit the amount thereof after receipt by the clearinghouse of the sums from those shippers having debits as calculated above. ARTICLE 7 MEASUREMENT AND TESTING 7.1 Crude Petroleum tendered to Transporter for transportation shall be measured and tested by a representative of Transporter prior to its receipt from Shipper. Shipper shall have the privilege of being present or represented at the measurement and testing. Quantities shall be measured by meters and calculated in accordance with applicable A.P.I. Manual of Petroleum Measurement Standards. All shipments of required specifications will be received and delivered as net standard
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Extract the exact clause related to "Post-Termination Services" from the excerpt above.

assistant: Not found.