Master Python Functions: From Basics to Time & Random Utilities

Hello everyone, I'm a Go advanced learner sharing some Python basics.

1. Function Overview

A function groups specific code into a reusable unit.

2. Function Definition and Invocation

Defining a function creates a tool you can later call to execute its code.

def test():
    print('----嘻嘻----')
    print('----这是我的第一个函数----')

Calling the function runs its body.

# Define a function

def test():
    print('----嘻嘻----')
    print('----这是我的第一个函数----')

# Call the function
test()

Output:

Python’s rich standard library provides many built‑in functions, making it popular among developers.

Time Functions

Printing timestamps and local time often helps with debugging.

1. Get current timestamp: time.time()

import time  # import time module
currentTime = time.time()
print("当前时间戳为:", currentTime)

2. Get local time tuple: time.localtime(time.time())

import time
localtime = time.localtime(time.time())
print("本地时间为 :", localtime)

import time
localtime = time.asctime(time.localtime(time.time()))
print("本地时间为 :", localtime)

Extended: datetime module

1. Format datetime to string

import datetime
now = datetime.datetime.now()
now.strftime('%Y-%m-%d %H:%M:%S')

2. Parse string to datetime

import datetime
t_str = '2019-04-07 16:11:21'
d = datetime.datetime.strptime(t_str, '%Y-%m-%d %H:%M:%S')
print(d)

strptime is a static method of the datetime class.

3. Date comparison with timedelta

The timedelta class represents a time interval and supports arithmetic.

import datetime
year = datetime.timedelta(days=365)
t_years = year * 10
new_years = t_years - year
print(t_years)
print(new_years)

date, time, and datetime objects can be added to or subtracted from timedeltas.

datetime1 = datetime2 + timedelta
timedelta = datetime1 - datetime2

This makes many operations convenient.

Calendar Function

import calendar
dar = calendar.month(2016, 8)
print("2016年8月份的日历:")
print(dar)

Random Number Functions

import random
a = random.uniform(1, 5)
print("a =", a)

b = random.randint(10, 50)
print("b =", b)

c = random.randrange(0, 51, 2)
print("c =", c)

3. Summary

This article explained how to define and call Python functions, introduced common time‑related functions, and demonstrated calendar and random utilities, providing practical code examples to help readers better understand and apply functions in Python.