Error connecting to SQL Server using pyodbc: Data source name not found and no default driver specified

Question

I'm encountering an issue while attempting to connect to a SQL Server database using the pyodbc library in Python. Here's the relevant code snippet:

import pyodbc 
cnxn = pyodbc.connect("Driver={SQL Server Native Client 11.0};"
                      "Server=localhost,1443;"
                      "Database=emp;"
                      "user=sam;"
                      "password=xyz@123;"
                      "Trusted_Connection=yes;")

import pyodbc 
cnxn = pyodbc.connect("Driver={SQL Server Native Client 17.0};"
                      "Server=localhost;"
                      "Database=emp;"
                      "user=sam;"
                      "password=xyz@123;"
                      "Trusted_Connection=yes;")

Tried both way also installed driver manually from microsoft based on code driver but no solution worked.

pyodbc.InterfaceError: ('IM002', '[IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified (0) (SQLDriverConnect)')