solve(codewars): Lazy Init [4 kyu]

Author: jestenough

services/codewars/katas/4_kyu/Lazy Init/README.md

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+# Lazy Init 
+
+How many times we create a python class and in the init method we just write:
+
+```
+self.name1 = name1
+self.name2 = name2
+.....
+```
+
+for all arguments.....
+
+How boring!!!!
+
+Your task here is to implement a metaclass that let this instantiation be done automatically. But let's see an example:
+```
+class Person(metaclass=LazyInit):
+  def __init__(self, name, age): pass
+```
+When we create a Person object like:
+```
+a_person = Person('John', 25)
+```
+The expected behavior will be:
+```
+print(a_person.name) # this will print John
+print(a_person.age)  # this will print 25
+```
+
+Obviously the number of arguments might be different from class to class.
+
+Don't worry about **kwargs you will never be given keyword arguments in this kata!!!
+
+A little hint: a decorator could help you out doing the job!!!
+
+Good luck lazy folks.....
+
+[Kata link](https://www.codewars.com/kata/59b7b43b4f98a81b2d00000a/)

services/codewars/katas/4_kyu/Lazy Init/solution_lazy_init.py

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+import inspect
+
+
+class LazyInit(type):
+    def __new__(cls, name, bases, attrs):
+        if init_method := attrs.get('__init__'):
+            init_parameters = inspect.signature(init_method).parameters
+            param_names = [name for name, param in init_parameters.items() if name != 'self']
+
+            def lazy_init(self, *args, **kwargs):
+                # TODO maybe write for kwargs too (although this is not provided for by the assignment)
+                for i, param_name in enumerate(param_names):
+                    setattr(self, param_name, args[i])
+
+            attrs['__init__'] = lazy_init
+
+        return super().__new__(cls, name, bases, attrs)

services/codewars/katas/4_kyu/Lazy Init/test_soluttion_lazy_jnit.py

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+from solution_lazy_init import LazyInit
+
+
+def test_lazy_init():
+    class Person(metaclass=LazyInit):
+        def __init__(self, name, age): pass
+
+    class Circle(metaclass=LazyInit):
+        def __init__(self, x, y, ray): pass
+
+    a_person = Person('Luke', 21)
+
+    assert a_person.name == 'Luke'
+    assert a_person.age == 21
+
+    a_circle = Circle(0, 0, 5)
+    assert a_circle.x == 0
+    assert a_circle.y == 0
+    assert a_circle.ray == 5
+
+    class Car(metaclass=LazyInit):
+        def __init__(self, model, color, plate, year): pass
+
+    class Nothing(metaclass=LazyInit):
+        def __init__(self, nothing): pass
+
+    a_car = Car('Ford Ka', 'Blue', 'AF329SZ', 1999)
+    a_nothing = Nothing('nothing')
+
+    assert a_car.model == 'Ford Ka'
+    assert a_car.color == 'Blue'
+    assert a_car.plate == 'AF329SZ'
+    assert a_car.year == 1999
+    assert a_nothing.nothing == 'nothing'