Added a constructor description with an example to constructor article (#26488)

* Added a constructor description with an example

* Changed text layout in Python constructor article

I learned how to make the text look nicer, so I changed the looks a bit :)

* Added clarification in python constructor guide

I added a short explanation about function overloading in python, why we only use one __init__ in a class.

* Grammatical, formatting and typo fixes

guide/english/python/object-oriented-programming/constructors/index.md

@@ -3,10 +3,50 @@ title: Constructors
 ---
 ## Constructors
 
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+A constructor is a special method (function) definition within a class. The constructor method is executed when an object is created, that is if the class has a constructor. If a constructor is not defined, it is automatically defined to be an empty function. In Python, it is only possible to have one constructor, which uses the special name -
+```python
+__init__(self)
+```
+and is defined under class variables in the class definition. In Python, we are only allowed to have one constructor, since function overloading is not used in the language. We can define a function with the same name multiple times but Python will use the function which was defined last, we can see it as overriding the previous function.
 
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+## Constructor example
 
+Let us define a `Cat` class, which has a tail. The number of legs, fur color and a race are added when an object is created.
+
+```python
+class Cat:
+  tail = True
+
+  def __init__(self, numLegs, colFur, race):
+    self.numberOfLegs = numLegs
+    self.colorOfFur = colFur
+    self.race = race
+```
+In this example we are forcing the user to enter information into the class by defining `__init__` to expect 3 parameters.
+```python
+bob = Cat(4, "gray", "siamese") // Works
+print(bob.tail) // True
+print(bob.colorOfFur) // gray
+
+bob = Cat() // Does not work
+```
+Let us define the cat class in a different way to not recieve initial information.
+```python
+class Cat:
+  tail = true
+
+  def __init__(self):
+    self.numberOfLegs = 4
+    self.colorOfFur = "gray"
+    self.race = "siamese"
+```
+Now the constructor is empty and no parameters are needed, the `self` parameter is always defined since that makes a reference to the object.
+
+```python
+bob = Cat() // Works now!
+
+bob = Cat(4, "gray", "siamese") // Does not work now!
+```
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