What is the typical time complexity of the function that converts a string to lowercase in Python?

The time complexity of the string to lowercase conversion function in Python, such as the str.lower() method, is typically O(n), where n is the length of the string.

This is because the function needs to iterate over each character in the string and convert it to lowercase if possible. Therefore, the execution time depends linearly on the size of the input data.

Example:

s = "Hello World!"
lower_s = s.lower()  # O(n), where n = len(s)
print(lower_s)  # hello world!