Human: Can you show me a Python function to default value if null. Assistant: 
Here is a Python function to default value if null

import numpy as np

def __default_value():
    """
    >>> __default_value()
    'default'
    """
    return 'default'

# Enter the default value
default_value = 'default'

# Calling the function
print((__default_value()))

#Example Output
# default

#Remember to inspect code for bugs.