IT hands-on

We create a class that inherits from the " Exception " class.  Our exception class is called " OurException " and it is raised when a v

The " @property " refers to a  python  decorator  - <i> a function that adds functionalities to another function without modifying its code </i> -. The  &qu

If a method has a  @classmethod  decorator, then it is a  class method . A  class method  has as its first argument " cls " which refers to the class

For our example, we define a class called " Member ": We subclass our class " Member " as below: Defining  __init__()  in our subclass wi

The  __setattr__() method is called in the background when we assign an attribute to a python  object. Below is our example, the " C ar " class: We s

To be able to access the attributes of a class while keeping these attributes safe from any unintended modification, we can to use properties . One way

Closures  are simply inner functions that could access variables from the enclosing function.  Closures  keep track of the enclosing function's varia

We have for example a class named " a " with no defined functions: The  dir()  function prints the methods and attributes -  inherited from the o

The  __str__()  function is called to give us the string representation of an object, it is called when we call the  print()  function on an object for ex

We use the  StopIteration  error in order to end an iteration as below: Sometimes we want to  instruct the  next()  method to return a value that would tell

Context managers  make it possible for us to manage our resources. When  python  enters a  context , it calls the  __enter__()  methods and it calls the  __exit

A  list  is an aggregate of elements enclosed in brackets. A  list comprehension  is constituted of: an expression.  a for loop.  an if clause within the loop

Below is one of the ways that we could use to combine two dictionaries into one: We could even use more than two dictionaries as we can see in the belo

Iterators  loop over existing elements in a list  for example. Generators  generate elements as we ask for them, which helps us not overload the memory in

Below are a couple of examples of how to turn a  dictionary  into a  list . Our first example used the  items()  method for form a  list  as we see below: Our s

Sometimes, we lose track of our variables inside big chunks of code. Python gives us the possibility to display variables depending on their  namespace

A  dictionary  usually maps a  key  to one  value . Sometimes, we need a  key  to be linked to  multiple values . We could do that using  lists  as you can see be

For example, we have the below dictionary  " d ". We could print the values  of our  dictionary , using the below code: Or by using this variation:

Enum  is python  object that represents a group of variables that are assigned a constant value. Below is a simple example -  we need to include the "

We could use the " while ... else " construct to break out of a " while " loop as soon as a condition is fulfilled. In the below exampl

When we pass a  mutable  default argument to a function -  here the  __init__()  funtion - , that accepts a list, changing the default  mutable  argument  will a

The  #ifdef  -  #endif statement dictates what parts of a program are taken into account during compilation, depending on whether a variable is defined or

For  classes  with small, simple data, we could save memory by using the  __slots__  attribute to the class.  For example the  Car  class below: With  __slots_

We could use  decorators  with parameters for example to control the flow of the execution of a  decorator  as we can see below: As we can see above, we co

We create an custom iterator function that we will use with a " for " loop: We use it as below: The " yield " function acts as a return