Python is an interpreted, object-oriented, high-level programming language with dynamic semantics developed by Guido van Rossum. It was originally released in 1991. Designed to be easy as well as fun, the name "Python" is a nod to the British comedy group Monty Python. Python has a reputation as a beginner-friendly language, replacing Java as the most widely used introductory language because it handles much of the complexity for the user, allowing beginners to focus on fully grasping programming concepts rather than minute details.
Python is used for server-side web development, software development, mathematics, and system scripting, and is popular for rapid application development (RAD) and as a scripting or glue language to tie existing components because of its high-level, built-in data structures, dynamic typing, and dynamic binding. Program maintenance costs are reduced with Python due to the easily learned syntax and emphasis on readability. Additionally, Python's support of modules and packages facilitates modular programs and reuse of code. Python is an open-source community language, so numerous independent programmers are continually building libraries and functionality for it.
Python use cases
- Creating web applications on a server
- Building workflows that can be used in conjunction with software
- Connecting to database systems
- Reading and modifying files
- Performing complex mathematics
- Processing big data
- Prototyping quickly
- Developing production-ready software
Professionally, Python is great for back-end web development, data analysis, artificial intelligence (AI), and scientific computing. Developers also use Python to build productivity tools, games, and desktop apps.
Python examples
Here are some examples illustrating the Python code syntax on how to create a loop and how to make a countdown timer.
Python loop
Loops are commonly used in programming languages to easily repeat code blocks. Python includes both “for” and “while” loops.
For loops are used with iterable objects, like lists or ranges. They allow you to repeat a block of code a fixed number of times, rather than writing that code over and over.
While loops execute a block of code until a certain condition is satisfied. For example, you may want to execute code when a given number is between 1 and 5. The loop will run while that statement is true, but if the user chooses a number outside that range, the loop will stop.
[While loop code in code block]
# program to display numbers from 1 to 5
# initialize the variable
i = 1
n = 5
# while loop from i = 1 to 5
while i <= n:
print(i)
i = i + 1
Output
1
2
3
4
5
Countdown timer
You can use a “while” loop along with some other Python functionality to create a simple countdown timer. Here's what the code looks like:
[Countdown timer code in code block]
import time
def countdown(time_sec):
while time_sec:
mins, secs = divmod(time_sec, 60)
timeformat = '{:02d}:{:02d}'.format(mins, secs)
print(timeformat, end='\r')
time.sleep(1)
time_sec -= 1
print("stop")
countdown(5)
- The divmod() method takes two numbers as arguments and returns two numbers where the first is the quotient and the second is the remainder
- end=’\r’ overwrites the output for each iteration of the while loop
- The time_sec value decreases after each iteration until the timer reaches zero
Features and benefits of Python
- Compatible with a variety of platforms, including Windows, Mac, Linux, Raspberry Pi, and others
- Uses a simple syntax comparable to the English language that lets developers use fewer lines than other programming languages
- Operates on an interpreter system that allows code to be executed immediately, fast-tracking prototyping
- Can be handled in a procedural, object-orientated, or functional way
Python syntax
- Somewhat similar to the English language, with a mathematical influence, Python is built for readability
- Unlike other languages that use semicolons or parentheses to complete a command, Python uses new lines for the same function
- Python defines scope (such as loops, functions, and classes) by relying on indentation using white space, rather than braces (or curly brackets)
Python flexibility
Python, a dynamically typed language, is especially flexible, eliminating hard rules for building features and offering more problem-solving flexibility with a variety of methods. It also allows users to compile and run programs right up to a problematic area because it uses run-time type checking rather than compile-time checking.
Challenges of Python
Python isn’t easy to maintain. One command can have multiple meanings depending on context because Python is a dynamically typed language. And, maintaining a Python app as it grows in size and complexity can be increasingly difficult, especially finding and fixing errors. Users will need experience to design code or write unit tests that make maintenance easier.
Speed is another challenge in Python. Its flexibility as a dynamically typed language requires a significant amount of referencing to land on a correct definition, slowing performance. This can be mitigated by using alternative implementation of Python (like PyPy).
Python and AI/ML
AI/ML researchers are fans of Python. Google TensorFlow, as well as other libraries (like scikit-learn and Keras), establish a foundation for AI/ML development because of the usability and flexibility it offers Python users. These libraries, and their availability, are critical because they enable developers to focus on growth and building.
Good to know
The Python Package Index (PyPI) is a repository of software for the Python programming language. PyPI helps users find and install software developed and shared by the Python community.