AI is the greatest technological revolution of our lifetimes, with far-reaching implications — both very good and very troubling — for every part of human society. As someone who teaches programming […] The post MIT just called for an educational revolution appeared first on LernerPython.

July and August are often when people take a break or go on vacation. But for me, this summer has been super busy, full of writing and improving LernerPython based […] The post AI seminars — just one of the big changes at LernerPython appeared first on LernerPython.

If you want to get better at Pandas, the hard part isn’t finding tutorials. It’s finding problems worth solving. Most exercises hand you a tidy little table of five rows […] The post Free real-world Pandas exercises, with solutions appeared first on LernerPython.

Once you import a Python module, a second import won’t reload it. That’s usually good. But what if you want to? (Common in development and debugging.) This forces the reload. The post importlib.reload: Reimporting a Python module during development appeared first on LernerPython.

You import a Python module with the variable you’ll define, not a filename. “import mymod” tells Python to find mymod.py in each dir in sys.path. The first directory is ” […] The post Python import: How a module name becomes a file on sys.path appeared first on LernerPython.

Over my 30+ years teaching Python, I’ve included practice exercises in all of my courses. And when I started to teach Git and Pandas, I made sure to include practice […] The post New: In-browser Python/Pandas/Git exercises, with AI support appeared first on LernerPython.

I just got back from PyCon US. It was delightful; I saw old friends, met new ones, gave a tutorial on decorators, and spoke at the education summit. I’m a […] The post Is Python becoming Pinyin? appeared first on LernerPython.

Set one Python class to inherit from another by putting the parent in (): Child.__bases__ # who does Child inherit from? The post Python class inheritance: Subclassing, __bases__, and isinstance appeared first on LernerPython.

Python uses attributes where other languages use different terms (and data structures): – Instance variable — attribute on an instance (self)– Class variable — attribute on a class– Method — […] The post Python attributes: Instance variables, class variables, and methods appeared first on LernerPyth...

Python methods are stored on a class, not an instance. Given x.m(), how does Python find it? The ICPO rule: – First, look for an attribute on the _i_nstance.– Not […] The post Python attribute lookup: The ICPO rule for finding methods appeared first on LernerPython.

By default, every Python class inherits from “object”. You can see this by checking the __bases__ attribute on a class: __bases__ is a tuple — hinting (correctly) that Python supports […] The post Python `__bases__`: Every class inherits from object appeared first on LernerPython.

Creating a Python class? You’re already using composition, the has-a relationship. How? When you assign to an attribute (e.g., self.name = name) in a Person class, you’re saying, “Person has-a […] The post Composition in Python classes: The has-a relationship appeared first on LernerPython.

Writing object-oriented Python? Don’t confuse the two core relationships: – has-a (“composition”). One object contains another. A Person has-a name. A Car has-a color.– is-a (“inheritance”). One class is similar […] The post Python composition vs inheritance: The has-a and is-a relationships appeare...

Python’s ternary operator is convenient, but easy to abuse: ‘A’ if s>=90 else ‘B’ if s>=80 else ‘C’ if s>=70 else ‘F’ Just because you CAN, doesn’t mean you SHOULD! […] The post Python ternary operator: When to use if-elif-else instead appeared first on LernerPython.

Want an if-else statement in your Python lambda? You can’t because it’s a statement. Instead, use the ternary operator: In other words: If it’s a string, return the value. If […] The post Python lambda if-else: Use the ternary operator instead appeared first on LernerPython.

In yesterday’s post, you saw Python’s ternary operator (an if-else expression). It’s useful in lambdas and comprehensions: VALUE_IF_TRUE if CONDITION else VALUE_IF_FALSE For example: The post Python’s ternary operator: Conditional expressions in comprehensions appeared first on LernerPython.

Defining a custom __format__ method in Python? Go bananas, if you want. For example (see image for full demo): The post Python `__format__`: Define your own format specification syntax appeared first on LernerPython.

Defining __format__ in a Python class? Check if the second argument is ”, meaning no format code: The post Python __format__: Detecting an empty format code appeared first on LernerPython.

Want your Python class to take custom format codes? Define __format__. This method returns self.x *except* with a :< format. Then it reverses self.x: The post Python `__format__`: Custom format codes for your own classes appeared first on LernerPython.

A Python value x in an f-string’s {} normally interpolates str(x), aka x.__str__. Want the repr instead, aka x.__repr__? Put !r after the value: f'{x}’ # returns str(x)f'{x!s}’ # also […] The post f-string conversion flags: Using !r to get repr instead of str appeared first on LernerPython.

Have a Python datetime, and want to print it? Use an f-string, and pass a strftime-style format: f'{now:%Y-%m-%d}’ # year-month-datef'{now:%Y-%m-%d %H:%M:%S}’ # year-month-date hour:min:sec # Easily integrate into user outputf’Today […] The post Formatting a Python datetime with f-strings and strfti...

Have a Python number, and want commas before every 3 digits? Use , in an f-string: Floats, too: Combine , and .2f: The post Thousands separators in Python f-strings: Format with commas appeared first on LernerPython.

Have a Python float, and want to show it as a percentage? Use % in an f-string The post Python float to percentage: Format with % in an f-string appeared first on LernerPython.

Want to display a Python float with a limited number of decimals? Use .nf as an f-string’s format specifier. n is the number of digits to show after the decimal: […] The post Formatting floats in Python f-strings: The .nf specifier appeared first on LernerPython.

Use Python f-strings and format specifiers to make quick-and-dirty tables: Output: a…….10bcd……2e…..3456 The post Python f-string format specifiers: Padding and aligning columns appeared first on LernerPython.

A Python f-string can have a “format specifier,” one or more characters after : that dictate the format. For example, you can use < ^ and > with an integer […] The post Python f-string format specifiers: Aligning and padding text appeared first on LernerPython.

Want to print a Python expression and its value? The modern way: All expressions work: The post Python f-string debugging: Printing expressions with = appeared first on LernerPython.

Remember, Python f-strings are strings: 1. Use f-strings anywhere you’d use strings, e.g., filenames and URLs2. You don’t have to print an f-string; you can store it.3. Don’t overuse them! […] The post Python f-strings are just strings: Use them anywhere appeared first on LernerPython.

Python f-strings are the best: – Put an f before the opening ‘ or “– Creates a regular string– Expressions in {} are evaluated/interpolated The post Python f-strings: Embedding expressions inside strings appeared first on LernerPython.

Want to round Python Pandas datetimes? You have 3 options: – dt.floor — earlier– dt.ceil – later– dt.round — nearest For example: The post Pandas datetime rounding: dt.floor, dt.ceil, and dt.round appeared first on LernerPython.