Python provides numerous built-in functions that are readily available to us at the Python prompt. Some of the functions like input() and print() are widely used for standard input and output operations respectively.
13. CLA
Example
1 #To display CLA
2
3 import sys
4
5 #Get the no. of CLA
6 n = len(sys.argv)
7
8 #Get the arguments
9 args = sys.argv
10
11 #Print the 'n'
12 print("No. Of CLA: ", n)
13
14 #print the arguments in one shot
15 print(args)
16
17 #Print the arguments one by one
18 for i in args:
19 print(i)
14. CLA
Parsing CLA
●
argparse module is useful to develop user-friendly programs
●
This module automatically generates help and usage messages
●
May also display appropriate error messages
15. CLA
Parsing CLA: Steps
● Step-1: Import argparse module
import argparse
● Step-2: Create an Object of ArgumentParser
parser = argparse.ArgumentParser(description="This program displays square of two numbers")
● Step-2a: If programmer does not want to display description, then above step can
be skipped
parser = argparse.ArgumentParser()
● Step-3: Add the arguments to the parser
parser.add_argument("num", type=int, help="Enter only int number.")
● Step-4: Retrieve the arguments
args = parser.parse_args()
● Step-4: Retrieve the arguments
● Step-5: Access the arguments
args.num