UNIT 1

• Python Essentials include Configuration, Python Environments, Variables, Function, Conditionals, Loops, Arrays, and Objects.
• Python Environments can be created and activated using the venv module.
• Variables in Python can be assigned using the assignment operator (=).
• Functions in Python can be defined using the def keyword.
• C++ and Java constructor names are the same with their class names.
• Constructor refers to a special function/method typically used to create/instantiate objects of classes.
• Python defines the constructor using the __init__ method.
• Instantiating objects in Python is done using the new operator.
• __init__ refers to the constructor of the class.
• Conditionals in Python can be expressed using if, elif, else.
• Loops in Python can be implemented using for, while, and range.
• Arrays in Python can be declared using the array() function.
• Objects in Python can be created using the class keyword.
• Looping in programming is almost always used because of the existence of arrays.
• Unlike Java and C++, we do not create/define the class properties/attributes/variables in a Python class outside the constructor.
• For loop using range and for loop using range are also used in Python.
• Unlike Java and C++, Python does not require you to state the variable type, such as int, bool, String, char, etc.
• A List can contains values, either homogenous or heterogeneous.
• Inside the Dog class, you can see two methods, init and bark.
• In Python, the keyword self is similar to “this” in Java, as it refers to the object/instantiated object.
• Another method is to append a whole list to another list, as seen in the example below.
• In Python, a collection created using square brackets is called a List.
• You can use negative indexing to access the opposite side of the list (starting from the end)
• One major difference here from other programming languages is the Python enables you to return multiple values, just separate them in a comma.
• In Python, they are called modules, and you can download and integrate them in your project.
• In Python, while loops and for loops are used.
• Classes are the templates used to create objects, as they contain the properties/attributes and methods.
• Use the command: Module name refers to the modules you want to add to your project.
• Functions can have default arguments, meaning if you didn’t provide a value for that parameter, it will resort on using the default value set in the function definition.
• Assigning and reassigning values in Python is done using the assignment operator =.
• Adding items to a list in Python can be done in two methods: using the built-in function of the list called append, which can add one item on the end of the list.
• Defining a function in Python requires the keyword def followed by the function name, a pair of parentheses that will contain the parameters passed on the function and a colon.
• In Python, we don’t specify the type of value we are returning, as you’ve seen on the previous example.
• Accessing each of the values inside the list/array becomes easier just because of loops.
• Defining a function is not enough to use it, you need to call it, like methods/functions in Java and C++.