human
Solve the following python programming problem given the following code:
@ pytest.fixture (scope = 'function') 
def eval_expr(env) : 
    from lektor.environment import Expression 
    def eval_expr(expr, **kwargs) : 
        expr = Expression (env, expr) 
        return expr.evaluate (** kwargs) 
return env 

    
    

    Fix the buggy line: return env
assistant
#Here is Python code to fix the buggy line: return env
.

return def eval_expr(