Fix docstring (#273)

* fix docstring

* add extra comments

Co-authored-by: Darcy Linde <{[email protected]}>

Author: Darcy-Linde

polygon/rest/trades.py

@@ -77,12 +77,13 @@ def get_last_crypto_trade(
         raw: bool = False,
     ) -> Union[CryptoTrade, HTTPResponse]:
         """
-        Get the most recent trade for a ticker.
+        Get the last trade tick for a cryptocurrency pair.
 
-        :param ticker: The ticker symbol of the asset
+        :param from_: The "from" symbol of the pair.
+        :param to: The "to" symbol of the pair.
         :param params: Any additional query params
         :param raw: Return raw object instead of results object
-        :return: Last trade
+        :return: Last crypto trade
         """
         url = f"/v1/last/crypto/{from_}/{to}"