This example assumes using Shotstack; is in scope and apiKey contains your Shotstack API key.
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varapiKey=Environment.GetEnvironmentVariable("SHOTSTACK_API_KEY")is{Length:>0}value?value:thrownewAssertInconclusiveException("SHOTSTACK_API_KEY environment variable is not found.");usingvarclient=newShotstackClient(apiKey);// The client has 4 sub-clients for different APIs.