How are arguments passed by value or by reference in Python?

Answer:

Python uses a mechanism, which is known as “Call-by-Object”, sometimes also called “Call by Object Reference” or “Call by Sharing”.

If you pass immutable arguments like integers, strings, or tuples to a function, the passing acts like Call-by-value. It behaves differently if we pass mutable arguments.

Let us see the code,

student={'Amlendra':28,'Pooja':25,'Amitosh':25}
def test(student):
   new={'Apoorv':5}
   student.update(new)
   print("Inside the function",student)
   return
test(student)
print("outside the function:",student)

Output:

Inside the function {‘Amlendra’: 28, ‘Amitosh’: 25, ‘Apoorv’: 5, ‘Pooja’: 25}
outside the function: {‘Amlendra’: 28, ‘Amitosh’: 25, ‘Apoorv’: 5, ‘Pooja’: 25}

Note: One important thing to note is, in Python every variable name is a reference. When we pass a variable to a function, a new reference to the object is created.