Adding first sample (#3)

* Adding first sample

* fixing .gitignore

Author: cosmicboy79

.gitignore

@@ -191,4 +191,7 @@ cython_debug/
 #  exclude from AI features like autocomplete and code analysis. Recommended for sensitive data
 #  refer to https://docs.cursor.com/context/ignore-files
 .cursorignore
-.cursorindexingignore
+.cursorindexingignore
+
+# PyCharm
+.idea

src/learning/decorating.py

@@ -0,0 +1,38 @@
+"""
+Decorators receive a function to be executed when it is called.
+However, some other action can be done before or after its execution.
+The idea is to encapsulate some behaviour that should happen on top of
+some operation and can be reused everywhere it is needed.
+"""
+from functools import wraps
+
+def log_function(func):
+    @wraps(func) # this ensures docstring, function name, arguments list, etc. are all copied
+                 # to the wrapped function - instead of being replaced with wrapper's info
+    def wrapper(*args, **kwargs):
+        print("Entering function {}".format(func.__name__))
+        result = func(*args, **kwargs)
+        print("Exiting function {}".format(func.__name__))
+        return result
+    return wrapper
+
+@log_function
+def add(a, b):
+    return a + b
+
+@log_function
+def subtract(a, b):
+    return a - b
+
+@log_function
+def multiply(a, b):
+    return a * b
+
+@log_function
+def divide(a, b):
+    return a / b
+
+print("Adding two numbers: " + str(add(1, 2)))
+print("Subtracting two numbers: " + str(subtract(8, 3)))
+print("Multiplying two numbers: " + str(multiply(5, 6)))
+print("Dividing two numbers: " + str(divide(45, 5)))