Update global variable through function bound with 'on_click'

Panel
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1

I am using a button to trigger a function. For this, I am using on_click(my_function).
While my_function may update some widgets, it should also modify a variable that is later accessed by another function. This variable is not stored in any widget.

Edit: After some more reading through the questions on Discourse, I think the better formulation of this question would be:

I have data which should be transformed by the user through a GUI. The data could be stored in a pd.DataFrame, or another data type. If different parts of my Panel GUI perform different transformations on the data - MUST I store the data in a class and have all transformation functions as class methods?

Is there a more elegant way of doing this? I am currently using global variables:

# %%
import panel as pn
pn.extension()

my_list = []

def create_list(event):
    global my_list
    my_list = [1, 2, 3, 4, 5]
    print(my_list)

def modify_list(event):
    global my_list
    my_list.append(6)
    print(my_list)

widget_number = pn.indicators.Number(
    name='Number',
    value=0,
    format='{value}'
)

widget_button_create_list = pn.widgets.Button(name='Create List')
widget_button_create_list.on_click(create_list)

widget_button_modify_list = pn.widgets.Button(name='Modify List')
widget_button_modify_list.on_click(modify_list)

pn.Column(widget_button_create_list, widget_button_modify_list).servable()

Edit: Related questions (turned up in search only after posting):

2

…I could pack everything into a class like so:

class MyApplication:
    def __init__(self):
        self.my_list = []

    def create_list(self, event):
        self.my_list = [1, 2, 3, 4, 5]
        print(self.my_list)

    def modify_list(self, event):
        self.my_list.append(6)
        print(self.my_list)

and then call the class methods from on_click()… is this the best way to go?

Edit: It does seem that “throwing everything into a single class” is a popular solution:

What is not quite clear to me is the point in making all objects in the class params instead of instance variables?