Archives: 2020/4 | PrimerPy

2020

04

19

Count element frequencies

How to count the frequencies of elements in a list? Convert to a dictionary with key is the element, value is the frequ

2020-04-19 Python

19

Sort Dictionary based on its values

How to sort a dictionary? It’s obvious to use the built-in sorted function, as it’s written in C and optimized already.

2020-04-19 Python

Python Data Structure

19

Named Tuple

For data with fixed format, they can be stored as tuples. Compared to dictionary, tuples save more space. However if we

2020-04-19 Python

Python Data Structure

19

Filter Data in List, Dictionary and Set

It’s a common operation to filter elements in list, dictionary and set. For loopdata = [-1, 2, 3, -4, 5] # filter out th

2020-04-19 Python

Python Data Structure

15

MRO: Understanding Multiple Inheritance in Python

While building a project in Django, it’s common to encounter multiple inheritance. For example, Django’s own ListView cl

2020-04-15 Python

Django Python MRO

15

Django Cookiecutter to create a project

Cookiecutter is a cli tool creating projects from templates.Cookiecutter Django is a good starting point to structure an

2020-04-15 Python

Django Python Cookiecutter

11

Inheritance, yield, contextmanager and rollback

Building a webapp with flask could involve a couple of more advanced topics in Python, Flask and SQLAlchemy Event and Ro

2020-04-11 Python

Python ORM Flask

06

Flask Multi-threading

Processes and threads are used to allocate computer resources in an optimal manner. Process A process is a unit for OS t

2020-04-06 Python

Python Flask Threading

06

AppContext vs. RequestContext and Flask vs. Request

In Flask, there are two types of context: AppContext, it’s a Flask object app = Flask(__name__) RequestContext, it’s

2020-04-06 Python

Python Flask Web Framework

05

Python Class Variables and Instance Variables

Understanding the difference between Class Var and Instance Var is fundamental to OOP. Class VarGiven a class Lang, as b

2020-04-05 Python

OOP Python Class

01

Flask: avoid circular import

One of the common mistakes using Flask is circular import.To avoid it, we can split one application file into three file

2020-04-01 Python

Python Flask Web Framework

01

Flask Jinja2 Template

Use Jinja2 template for Flask frontend rendering. Pass VariablesThere are two ways passing variables via Jinja2 pass va

2020-04-01 Python

Python Flask Web Framework Jinja2