<human>:  i want to return none if input to my function is empty.
<bot>: Here is a Python function to return none if input to my is empty

import re

def is_empty(input):
  """
  Returns None if input is empty.
  """
  if input:
    return input
  else:
    return None

# Enter the string
string = "hello"

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

#Example Output
# hello

#Remember to inspect code for bugs.