def backends(request):
from caproto import select_backend, backend
def switch_back():
select_backend(initial_backend)
initial_backend = backend.backend_name
request.addfinalizer(switch_back)
try:
select_backend(request.param)
except KeyError:
raise pytest.skip(f'backend {request.param} unavailable')
def switch_back():
select_backend(initial_backend)