It's a local custom.

这是当地的风俗习惯。

《牛津词典》

The Works shall be measured net, notwithstanding any general or local custom, except where otherwise provided for in the contract.

无论通常的和当地的习惯如何，工程计量应该计量净值，但合同另有规定的除外。

youdao

The Works shall be measured net, notwithstanding any general or local custom, except where otherwise provided for in the contract.

无论通常的和当地的习惯如何，工程计量应该计算净值，但合同另有规定的除外。

youdao

Chicago was preparing for its own big parade and an eye-catching local custom: dying the Chicago River green.

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Two days later, in the capital of Khartoum, we walked the streets, rode a city bus to the confluence of the Blue and White Niles, chatted with dozens of Sudanese, and, after dark, found a street-food stall for a meal of goat, eaten with our fingers as per local custom.

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This changed in 2004 with the arrival of Bill Courtney, a local dealer in custom lumber, who volunteered to coach the team.

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