Rewrite all rest examples according to v3.0.0b3's changes.

examples/rest/public/pulse_endpoints.py

@@ -1,20 +1,20 @@
 # python -c "import examples.rest.public.pulse_endpoints"
 
 import datetime
-
 from typing import List
 
-from bfxapi import Client, PUB_REST_HOST
-
+from bfxapi import Client
 from bfxapi.types import PulseMessage, PulseProfile
 
-bfx = Client(rest_host=PUB_REST_HOST)
+bfx = Client()
 
 # POSIX timestamp in milliseconds (check https://currentmillis.com/)
 end = datetime.datetime(2020, 5, 2).timestamp() * 1000
 
 # Retrieves 25 pulse messages up to 2020/05/02
-messages: List[PulseMessage] = bfx.rest.public.get_pulse_message_history(end=end, limit=25)
+messages: List[PulseMessage] = bfx.rest.public.get_pulse_message_history(
+    end=end, limit=25
+)
 
 for message in messages:
     print(f"Message author: {message.profile.nickname} ({message.profile.puid})")
@@ -23,4 +23,7 @@ for message in messages:
 
 profile: PulseProfile = bfx.rest.public.get_pulse_profile_details("News")
 URL = profile.picture.replace("size", "small")
-print(f"<{profile.nickname}>'s profile picture: https://s3-eu-west-1.amazonaws.com/bfx-pub/{URL}")
+print(
+    f"<{profile.nickname}>'s profile picture:"
+    f" https://s3-eu-west-1.amazonaws.com/bfx-pub/{URL}"
+)