Updating ODBC driver version reference

Also adding code comment examples of other common server connection values.

Author: David-Engel

docs/connect/python/pyodbc/step-3-proof-of-concept-connecting-to-sql-using-pyodbc.md

@@ -34,11 +34,14 @@ This example should be considered a proof of concept only.  The sample code is s
 ```python
 
 import pyodbc 
+# Some other example server values are
+# server = 'localhost\sqlexpress' # for a named instance
+# server = 'myserver,port' # to specify an alternate port
 server = 'tcp:myserver.database.windows.net' 
 database = 'mydb' 
 username = 'myusername' 
 password = 'mypassword' 
-cnxn = pyodbc.connect('DRIVER={ODBC Driver 13 for SQL Server};SERVER='+server+';DATABASE='+database+';UID='+username+';PWD='+ password)
+cnxn = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};SERVER='+server+';DATABASE='+database+';UID='+username+';PWD='+ password)
 cursor = cnxn.cursor()
 
 ```