Efficient Element Deletion and Copy Creation in Python Dictionaries

In Python, deleting elements from dictionaries can be done for diverse reasons. To permanently remove an item from the original dictionary, the del statement should be utilized:

del d[key]

However, to obtain a new dictionary without modifying the original version, a copy must be created beforehand. Employing the dict() constructor achieves this by performing a shallow copy. For instance:

def removekey(d, key):
    r = dict(d)
    del r[key]
    return r

It's crucial to note that the dict() constructor only creates a shallow copy. If a deep copy is required, the copy module should be consulted. Moreover, creating a copy for every dictionary modification introduces linear time and space complexities. Therefore, for large dictionaries, alternative data structures like HAMT (Hierarchical Associative Memory Tree) may be more appropriate.