Jack Smith jacksmith15

def a_long_function():
    ... # do some stuff
    # Something is broken around here, we want to poke around, so we add this:
    import pdb;pdb.set_trace()
    ... # other stuff

When we run the code, it stops at the import pdb;pdb.set_trace() and gives us control over the program. We can rewrite the code as its executing!

EAFP vs LBYL

This illustrates the difference between EAFP (Easier to ask forgiveness than permission) vs LBYL (Look before you leap).

To illustrate, consider a function which gets a value from a dictionary by key, returning a default if not present. This is the function implemented in each style:

Look before you leap:

def get(dictionary, key, default):
 if key in dictionary:

Some examples of CSV operations in Python

Using standard library

The following uses the csv standard library, specifically DictReader, to parse a CSV as a list of dictionaries.

DictReader accepts the file handler, and automatically parses the header for the field names. It can then be iterated to get each row of the CSV. This happens lazily by default, but since we want the whole thing, we load it into a list (which means we can let the file close.

import csv

Type Annotations

Full documentation is here.

Type annotations do not affect runtime, but allow other tools to statically analyse you code for errors. The offical checker is MyPy, which has an IntelliJ extension.

Variable annotations

Type annotations come after the variable/attribute declaration (unlike Java):

foo: int
foo = 1

Release guide

Developer-oriented guide to named release branching process.

This concerns how delivery teams interact with the release process via a branching strategy rather than the wider release process.

Steps

Release candidate branches may be merged into master once the previous named release completes E2E testing.
- Mark to own updates on completion of E2E testing.

Developers to own:

	"""Very rough solution to problem posed @gecBurton.

	https://gist.github.com/gecBurton/9b74f005d715317f70bb61528f05b29a
	"""
	from collections import defaultdict
	from typing import Any, Dict, List


	INDENT = " "

	from typing import AsyncIterator

	from pydantic import BaseModel
	from radish import RedisInterface, Database


	class User(BaseModel):
	id: int
	name: str

	from random import randint

	import faust
	from simple_settings import settings

	app = faust.App(**settings.FAUST)


	source_topic = app.topic("source", value_type=int)

	from sys import argv, exit
	import csv


	def main():

	if len(argv) != 3:
	print("Usage: python dna.py filename.csv filename.txt")
	exit(1)
	people = []

	from typing import List, Union

	from statham.dsl.constants import Maybe
	from statham.dsl.elements import (
	AnyOf,
	Array,
	Boolean,
	Integer,
	Null,
	Number,