use asyncio.run and update requirements to py3.7

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = edge-tts
-version = 0.0.4
+version = 0.0.5
 author = rany
 author_email = ranygh@riseup.net
 description = Microsoft Edge's TTS
@@ -19,7 +19,7 @@ package_dir=
     = src
 packages = find:
 scripts = bin/edge-playback
-python_requires = >=3.6
+python_requires = >=3.7
 install_requires =
     requests
     websockets>=9.1

src/edgeTTS/__init__.py

@@ -151,7 +151,7 @@ def terminator(signo, stack_frame): sys.exit()
 def main():
     signal.signal(signal.SIGINT, terminator)
     signal.signal(signal.SIGTERM, terminator)
-    asyncio.get_event_loop().run_until_complete(_main())
+    asyncio.run(_main())
 
 if __name__ == "__main__":
     main()