[LARGE] updating all tests and API

tests/conftest.py

@@ -1,19 +0,0 @@
-# content of conftest.py
-
-import pytest
-
-
-def pytest_addoption(parser):
-    parser.addoption(
-        "--runslow", action="store_true", default=False, help="run slow tests"
-    )
-
-
-def pytest_collection_modifyitems(config, items):
-    if config.getoption("--runslow"):
-        # --runslow given in cli: do not skip slow tests
-        return
-    skip_slow = pytest.mark.skip(reason="need --runslow option to run")
-    for item in items:
-        if "slow" in item.keywords:
-            item.add_marker(skip_slow)