PropCheck.property_setup

You're seeing just the macro property_setup, go back to PropCheck module for more information.
Link to this macro

property_setup(setup_fun, prop)

View Source (macro)

Adds a setup function to the property which will be called before the first test.

This function has to return a finalize function of arity 0, which should return the atom :ok, that will be called after the last test. It is possible to use multiple property_setup macros on the same property.