__hash method: The time complexity of calculating the hash code for the given key is O(n), where n is the length of the key. The method iterates through each character of the key and calculates the ASCII value using ord, resulting in linear time complexity.
set method: The time complexity of inserting a key-value pair in the hashtable is O(1) on average. However, in the worst-case scenario, when there are many collisions at the same index, the time complexity can become O(n), where n is the number of key-value pairs in the same bucket (linked list traversal).
get method: The time complexity of retrieving a value based on the key is O(1) on average. However, in the worst-case scenario, when there are many collisions at the same index, the time complexity can become O(n), where n is the number of key-value pairs in the same bucket (linked list traversal).
has method: The time complexity of checking if a key exists in the hashtable is the same as the get method, which is O(1) on average and O(n) in the worst-case scenario due to linked list traversal.
keys method: The time complexity of returning a list of all keys present in the hashtable is O(1), as it returns a pre-stored list of keys.
The space complexity of the HashTable class is O(size + n), where size is the size of the bucket array (number of buckets), and n is the number of key-value pairs in the hashtable.
python Python/code_challenge30/hashtable/hashtable.py
for testing: pytest Python/code_challenge30/tests/test_hashtable.py