Human: how to use dictionary funtion to replace in. Assistant: 
Here is a Python function to use dictionary function to replace in a dictionary

import copy

def replace_dict(d, key, value):
    """
    Replaces the value of key in dictionary d with value.
    """
    d[key] = value

# Enter the dictionary
d = {"a": 1, "b": 2, "c": 3}

# Enter the key and value
key = "a"
value = 4

# Calling the function
d2 = copy.deepcopy(d)
d2 = replace_dict(d2, key, value)

# Printing the dictionary
print(d2)

#Example Output
# None

#Remember to inspect code for bugs.