Update quotes.py docstring (#532)

* Update quotes.py docstring

* Terminology fix - timeframe should be time intervals for Bars, time period should be the start and end times for which Bars are accumulated

alpaca/data/models/quotes.py

@@ -16,10 +16,10 @@ class Quote(BaseModel):
         timestamp (datetime): The time of submission of the quote.
         bid_price (float): The bidding price of the quote.
         bid_size (float): The size of the quote bid.
-        bid_exchange (Optional[str, Exchange]): The exchange the quote bid originates. Defaults to None.
+        bid_exchange (Optional[Union[str, Exchange]]): The exchange the quote bid originates. Defaults to None.
         ask_price (float): The asking price of the quote.
         ask_size (float): The size of the quote ask.
-        ask_exchange (Optional[str, Exchange]): The exchange the quote ask originates. Defaults to None.
+        ask_exchange (Optional[Union[str, Exchange]]): The exchange the quote ask originates. Defaults to None.
         conditions (Optional[Union[List[str], str]]): The quote conditions. Defaults to None.
         tape (Optional[str]): The quote tape. Defaults to None.
     """

alpaca/data/requests.py

@@ -133,9 +133,9 @@ class OptionBarsRequest(BaseBarsRequest):
 
     Attributes:
         symbol_or_symbols (Union[str, List[str]]): The ticker identifier or list of ticker identifiers.
-        timeframe (TimeFrame): The period over which the bars should be aggregated. (i.e. 5 Min bars, 1 Day bars)
-        start (Optional[datetime]): The beginning of the time interval for desired data. Timezone naive inputs assumed to be in UTC.
-        end (Optional[datetime]): The end of the time interval for desired data. Defaults to now. Timezone naive inputs assumed to be in UTC.
+        timeframe (TimeFrame): The length of time (also known as time interval) for which each Bar represents (i.e. 5 Min bars, 1 Day bars).
+        start (Optional[datetime]): The beginning of the time period for desired data. Timezone naive inputs assumed to be in UTC.
+        end (Optional[datetime]): The end of the time period for desired data. Defaults to now. Timezone naive inputs assumed to be in UTC.
         limit (Optional[int]): Upper limit of number of data points to return. Defaults to None.
         sort (Optional[Sort]): The chronological order of response based on the timestamp. Defaults to ASC.
     """