Development vs Release Python Code

I am currently developing a Python application (for PhD research) which I continually performance test, simply by recording the runtime of various parts.

A lot of the code is related only to the testing environment and would not exist in the real world application, at the moment I comment out these parts when testing. This requires me to remember which calls refer to test only components (they are quite interleaved so I cannot group the functionality).

I was wondering if there was a better solution to this, the only idea I have had so far is creation of a 'mode' boolean and insertion of If statements, though this feels needlessly messy. I was hoping there might be some more standardised testing method that I am naive of.

Thank you in advance