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A utility like Unix seq (command-line), in Python (Python recipe) by Vasudev Ram
ActiveState Code (http://code.activestate.com/recipes/580744/)

This recipe shows how to create a utility like Unix seq (command-line), in Python. seq is described here:

https://en.wikipedia.org/wiki/Seq_(Unix)

but briefly, it is a command-line utility that takes 1 to 3 arguments (some being optional), the start, stop and step, and prints numbers from the start value to the stop value, on standard output. So seq has many uses in bigger commands or scripts; a common category of use is to quickly generate multiple filenames or other strings that contain numbers in them, for exhaustive testing, load testing or other purposes. A similar command called jot is found on some Unix systems.

This recipe does not try to be exactly the same in functionality as seq. It has some differences. However the core functionality of generating integer sequences is the same (but without steps other than 1 for the range).

More details and sample output are here:

https://jugad2.blogspot.in/2017/01/an-unix-seq-like-utility-in-python.html

The code is below.

Python, 34 lines
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'''
seq1.py
Purpose: To act somewhat like the Unix seq command.
Author: Vasudev Ram
Copyright 2017 Vasudev Ram
Web site: https://vasudevram.github.io
Blog: https://jugad2.blogspot.com
Product store: https://gumroad.com/vasudevram
'''

import sys

def main():
    sa, lsa = sys.argv, len(sys.argv)
    if lsa < 2:
        sys.exit(1)
    try:
        start = 1
        if lsa == 2:
            end = int(sa[1])
        elif lsa == 3:
            start = int(sa[1])
            end = int(sa[2])
        else: # lsa > 3
            sys.exit(1)
    except ValueError as ve:
        sys.exit(1)

    for num in xrange(start, end + 1):
        print num, 
    sys.exit(0)
    
if __name__ == '__main__':
    main()
Tags: bash, command, commandline, linux, script, seq, sequence, shell, unix, utilities, utility