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Python Python Sequences Sequence Iteration Iterating over Ranges

YI JIANG
YI JIANG
3,424 Points

why it returns to none

Write a for loop that iterates over a range with a stop value of 10 (assume the start value is 0 and the step value is 1). The body of the for loop should append the current value to the provided list called my_list. To append a value to a list, use the syntax my_list.append(val).

my_list = [] for val in range(10): print(my_list.append(val))

iterating_ranges.py
my_list = []

1 Answer

From the python docs:

You might have noticed that methods like insert, remove or sort that only modify the list have no return value printed – they return the default None. This is a design principle for all mutable data structures in Python.