In Python, a constant list is a list that cannot be modified after it is created. This can be achieved by using the tuple data type instead of the list data type. Here is an example:
# creating a constant list
my_list = (1, 2, 3, 4, 5)
# trying to modify the constant list will raise an error
my_list[0] = 10
Output:
TypeError: 'tuple' object does not support item assignment
As you can see, trying to modify the constant list my_list by changing its first element, raises a TypeError because tuples are immutable.
Another way to create a constant list in Python is by using the frozenset function. Here is an example:
# creating a constant list
my_list = frozenset([1, 2, 3, 4, 5])
# trying to modify the constant list will raise an error
my_list.add(6)
Output:
AttributeError: 'frozenset' object has no attribute 'add'
As you can see, trying to modify the constant list my_list by adding an element to it, raises an AttributeError because frozensets are immutable.
Therefore, to create a constant list in Python, you can use either tuple or frozenset data types.