Human: Write me a Python function to drop a key in dictionary. Assistant: 
Here is a Python function to drop a key in dictionary

import collections

def drop_key(dictionary, key):
    """Drop a key from a dictionary.

    If the key is not in the dictionary, it is created.
    """
    if key not in dictionary:
        dictionary[key] = 0
    else:
        del dictionary[key]

# Enter the dictionary
dictionary = {"key1": 1, "key2": 2}

# Enter the key
key = "key1"

# Calling the function
print((drop_key(dictionary, key)))

#Example Output
# None

#Remember to inspect code for bugs.