Human: Python function to go back up a line output 3 output 3 output 3. Assistant: 
Here is a Python function to go back up a line output 3 output 3

import re

def go_back_3(line):
    """
    :param line: line to be go back up
    :return: go back up 3 lines
    :rtype: str
    """
    return line[:-3] + "\n" + line[-3:]

# Enter the string
string = "hello\nworld"

# Calling the function
print((go_back_3(string)))

#Example Output
# hello
# wo
# rld

#Remember to inspect code for bugs.