I don't know if this is the appropriate place to ask but is there a simple guide on how I can actually run a unit test using pytest on a solid? I have tried using the code examples in the GitHub repo but always end up with

solid_name = 'generate_date_suffix'

    def assert_in_composition(solid_name):
        if len(_composition_stack) < 1:
            raise DagsterInvariantViolationError(
                'Attempted to call solid "{solid_name}" outside of a composition function. '
                'Calling solids is only valid in a function decorated with '
>               '@pipeline or @composite_solid.'.format(solid_name=solid_name)
            )
E           dagster.core.errors.DagsterInvariantViolationError: Attempted to call solid "generate_date_suffix" outside of a composition function. Calling solids is only valid in a function decorated with @pipeline or @composite_solid.