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Thanks for your edits to the Mariupol article. However, is it really a good idea to substitute Ukrainian for Russian in the "alt" tabs? I don't live in and haven't visited Mariupol, but w:Mariupol says this:
The city is largely and traditionally Russophone, while ethnically the population is divided about evenly between Russians and Ukrainians.
I'm presuming way more Ukrainians in Mariupol speak Russian than vice versa. If you like, you could add the Ukrainian names for everything and separate the two with a comma or semicolon, resulting in something like this:
name=Mariupol International Airport | alt=Международный аэропорт "Мариуполь" (Russian), Міжнародний аеропорт "Маріуполь" (Ukrainian)
Does that seem like a good solution to you?
All the best,