Put @pytest.mark.<identifier> above the test method.

Run $ pytest -v -m <identifier>.

<indentifier> can be anything you choose.

For example, the a test file may look like this:

import pytest

@pytest.mark.focus
def first_test():
  # do a test here
  print('first test')

def second_test():
  # do another test here
  print('second test')

And then you can run the following command: pytest -v -m focus. first test should be printed to stdout, indicating only the first test was run.

Don’t forget to import pytest.

The -v flag will make the output more verbose so you can see everything that is going on.

The -m flag expects one argument: a mark expression. It will tell pytest to only run tests matching the identifier given.