import sys
from datetime import datetime

TEMPLATE = """
Title: {title}
Date: {year}-{month}-{day} {hour}:{minute:02d}
Modified: 
Author: 
Category: 
Tags: 



"""


def make_entry(title):
    today = datetime.today()
    title_no_whitespaces = title.lower().strip().replace(' ', '-')
    f_create = "content/{}_{:0>2}_{:0>2}_{}.md".format(
        today.year, today.month, today.day, title_no_whitespaces)
    t = TEMPLATE.strip().format(title=title,
                                year=today.year,
                                month=today.month,
                                day=today.day,
                                hour=today.hour,
                                minute=today.minute)
    with open(f_create, 'w') as w:
        w.write(t)
    print("File created -> " + f_create)


if __name__ == '__main__':

    if len(sys.argv) > 1:
        make_entry(sys.argv[1])
    else:
        print "No title given"

import sys
from datetime import datetime

TEMPLATE = """
Title: {title}
Date: {year}-{month}-{day} {hour}:{minute:02d}
Modified: 
Author: 
Category: 
Tags: 



"""


def make_entry(title):
    today = datetime.today()
    title_no_whitespaces = title.lower().strip().replace(' ', '-')
    f_create = "content/{}_{:0>2}_{:0>2}_{}.md".format(
        today.year, today.month, today.day, title_no_whitespaces)
    t = TEMPLATE.strip().format(title=title,
                                year=today.year,
                                month=today.month,
                                day=today.day,
                                hour=today.hour,
                                minute=today.minute)
    with open(f_create, 'w') as w:
        w.write(t)
    print("File created -> " + f_create)


if __name__ == '__main__':

    if len(sys.argv) > 1:
        make_entry(sys.argv[1])
    else:
        print("No title given")

Convert script to Python 3
Convert script to Python 3

Changed print function in main to be Python 3 compatible