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I'm playing with Azure Functions and the main method is 

def main(req: func.HttpRequest) -> func.HttpResponse:

Can someone please break down every part of this and explain what it means. Specifically what does req: func.HttpRequest mean, is it forcing some data type for the parameter? And what does -> func.HttpResponse mean, is it forcing a return type?

I've never seen this syntax in Python before.

Nic
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    The phrase you should Google is: Python Annotations – dfundako Nov 12 '19 at 21:39
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    You are seeing annotations and type hinting. `req` is a required positional argument. `: func.HttpRequest` is a type hint telling the user what `req` should be. In this case an HTTP request object. The trailing bit `-> func.HttpResponse` is another annotation telling you what the function returns. In this case an HTTP Response object. – James Nov 12 '19 at 21:39
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    [Typing](https://docs.python.org/3/library/typing.html) – Cory Kramer Nov 12 '19 at 21:40

1 Answers1

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It defines a function named main, which takes one parameter named req that is of type func.HttpRequest, and returns a value of type func.HttpResponse.

John Gordon
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