TypeError coercing to Unicode need string or buffer NoneType found

This error occurs when you are trying to perform a string operation on a variable that has a value of None.

To fix this error, you need to ensure that the variable has a string value before performing any string operations on it. One way to do this is to check if the variable is None using an if statement and then assigning a default value to it if it is None.

For example:

my_var = None

if my_var is None:
    my_var = "default value"

# now my_var has a string value and can be used in string operations

Alternatively, you can check for None using a ternary operator:

my_var = None

my_var = "default value" if my_var is None else my_var

# now my_var has a string value and can be used in string operations

By ensuring that the variable has a string value before performing any string operations on it, you can avoid the TypeError.