how to check how many items are in a list python

1list_a = ["Hello", 2, 15, "World", 34]
2
3number_of_elements = len(list_a)
4
5print("Number of elements in the list: ", number_of_elements)
6

1def length(items):
2    how_many = 0
3    for i in items:
4        how_many += 1
5    return how_many
6a = [8,59,69,49,78,4,7]
7print(length(a))

1list1 = [2,3,4,3,10,3,5,6,3]
2elm_count = list1.count(3)
3print('The count of element: 3 is ', elm_count)

1List = ["Elephant", "Snake", "Penguin"]
2
3print(len(List))
4
5#	With the 'len' function Python counts the amount of elements 
6#	in a list (The length of the list).
7#	In this case the output is '3' because there are 3 elements in the list. 

1my_list = [1,2,3,4,5,6,7,8,9,10]
2
3length_of_list = len(my_list)