len()
function
Returns the number of items in a container (string, list, tuple, dict, set, etc.).
Syntax
len(s)
Example
python
print(len('hello')) # 5
print(len([1, 2, 3])) # 3
print(len({'a': 1})) # 1
print(len((1, 2, 3, 4))) # 4
print(len({1, 2, 3})) # 3