vlad-bezden

To uninstall all packages in current venv

On Linux:

$ pip freeze > args | pip uninstall -y -r args | rm args

On Windows:

vlad-bezden

"""
Project structure:

demo_reader
  src
    demo_reader
      compressed
        __init__.py
        bzipped.py
        gzipped.py

vlad-bezden

"""
Flatten a List

There is a list which contains integers or other nested lists which may contain yet
more lists and integers which then may contain more lists ...
You should put all of the integer values into one flat list. The order should be as it
was in the original list with string representation from left to right.

Your code should be shorter than 140 characters (with whitespaces).

vlad-bezden

: create virtual environment
python -m venv ./venv

: create activate.bat file
echo .\venv\scripts\activate.bat > activate.bat

: activate virtual env
call activate.bat

: update pip

vlad-bezden

file = "some_file_path.csv"

# Option #1 using readlines(). It will create list of lines
with open(file, "r") as reader:
    lines = reader.readlines()

# Option #2. Read line by line and add to the list
with open(file, "r") as reader:
    lines = []
    for line in reader:

vlad-bezden

vlad-bezden

vlad-bezden

"""
An example of how to annotate cls return type class in inheritance using mypy
in order to escape error `AttributeError: type object 'A' has no attribute 'bazz'`

Here is what we done:
* The type variable TA is used to denote that return values might be an
instances of subclasses of A.
* Specify that A is an upper bound for TA.
Specifying bound means that TA will only be A or one of its subclasses.
This is needed to properly restrict the types that are allowed.

vlad-bezden

"""
Creates 2D matrix
"""


def matrix(rows, cols, start=0):
    return [[c + start + r * cols for c in range(cols)] for r in range(rows)]


assert matrix(2, 3, 1) == [[1, 2, 3], [4, 5, 6]]

vlad-bezden

"""
List allocation with teh same value using different techniques

The winner is [value] * times by between 15-25 times 
"""

from timeit import timeit
from itertools import repeat