Dictionary behaves like a global variable

A dictionary that I pass as an argument seems to behave like a global variable. This was a surprise to me but it seems that it makes sense in Python (see for instance this topic). However, I'm very surprised that I get a different behavior for a different type of variable. Let assume that I have a script main.py that calls two functions from a module.

import mymodule

an_int = 42
a_dict = {'value':42}

mymodule.print_and_reassign(a_dict, an_int)
mymodule.print_again(a_dict, an_int)

with my modules.py containing the following functions

def print_and_reassign(a_dict, an_int):

    # Dictionary
    print(f"Dictionary value: {a_dict['value']}")
    a_dict['value']=970

    # Integer
    print(f"Integer value: {an_int}")
    an_int=970


def print_again(a_dict, an_int):

    # Dictionary
    print(f"Dictionary value: {a_dict['value']}")

    # Integer
    print(f"Integer value: {an_int}")

By running main.py, I get the following results

Dictionnary value: 42
Integer value: 42
Dictionnary value: 970
Integer value: 42

This is very counterintuitive to me. Why does the dictionary changed while the integer remains unchanged?

source https://stackoverflow.com/questions/73547620/dictionary-behaves-like-a-global-variable