Improve doc: The data is cached for 1 hour

Author: BostX

README.md

@@ -40,7 +40,10 @@ GET /recovered
 
 ## Data
 
-The data is retrieved programatically and re-formatted from the [2019 Novel Coronavirus (nCoV) Data Repository, provided by JHU CCSE](https://github.com/CSSEGISandData/2019-nCoV).
+The data comes from the [2019 Novel Coronavirus (nCoV) Data Repository, provided
+by JHU CCSE](https://github.com/CSSEGISandData/2019-nCoV). It is
+programmatically retrieved, re-formatted and stored in the cache for one hour.
+
 
 ## Prerequisites
 

app/data/__init__.py

@@ -11,7 +11,7 @@
 @cached(cache=TTLCache(maxsize=1024, ttl=3600))
 def get_data(category):
     """
-    Retrieves the data for the provided type.
+    Retrieves the data for the provided type. The data is cached for 1 hour.
     """
 
     # Adhere to category naming standard.