Replace get_event_loop with single methods in conftest (#4)

Author: vittoriozamboni

tests/conftest.py

@@ -6,8 +6,16 @@
 
 @pytest.fixture(scope="session")
 def event_loop():
-    """Force the pytest-asyncio loop to be the main one."""
-    loop = asyncio.get_event_loop()
+    """
+    Force the pytest-asyncio loop to be the main one.
+    If there is no running event loop, create one and
+    set as the current one.
+    """
+    try:
+        loop = asyncio.get_running_loop()
+    except RuntimeError:
+        loop = asyncio.new_event_loop()
+        asyncio.set_event_loop(loop)
     yield loop