How to test a Python script with an input file filled with testcases?

input, python

Solution

So the script normally takes test cases from stdin, and now you want to test using test cases from a file?

If that is the case, use the `<` redirection operation on the cmd line:

my_script < testcases.in

Problem

I'm participating in online judge contests and I want to test my code with a .in file full of testcases to time my algorithm. How can I get my script to take input from this .in file?

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