What does error TypeError: ‘NoneType’ object is not iterable mean? I am getting it on this Python code: def write_file(data, filename): # creates file and writes list to it with open(filename, ‘wb’) as outfile: writer = csv.writer(outfile) for row in data: # ABOVE ERROR IS THROWN HERE writer.writerow(row) 11 Answers 11
My editor warns me when I compare my_var == None, but no warning when I use my_var is None. I did a test in the Python shell and determined both are valid syntax, but my editor seems to be saying that my_var is None is preferred. Is this the case, and if so, why? 6 … Read more
This was my source I started with. My List L = [0, 23, 234, 89, None, 0, 35, 9] When I run this : L = filter(None, L) I get this results [23, 234, 89, 35, 9] But this is not what I need, what I really need is : [0, 23, 234, 89, 0, … Read more
I keep getting an error that says AttributeError: ‘NoneType’ object has no attribute ‘something’ The code I have is too long to post here. What general scenarios would cause this AttributeError, what is NoneType supposed to mean and how can I narrow down what’s going on? 10 Answers 10
I have a method that sometimes returns a NoneType value. So how can I question a variable that is a NoneType? I need to use if method, for example if not new: new = ‘#’ I know that is the wrong way and I hope you understand what I meant. 7 s 7 So how … Read more
I need a way to get a dictionary value if its key exists, or simply return None, if it does not. However, Python raises a KeyError exception if you search for a key that does not exist. I know that I can check for the key, but I am looking for something more explicit. Is … Read more
This question already has answers here: Python `if x is not None` or `if not x is None`? [closed] (9 answers) Closed 7 years ago. Out of these not None tests. if val != None: if not (val is None): if val is not None: Which one is preferable, and why? 4 s 4
Closed. This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 1 year ago. Improve this question I’ve always thought of the if not x is None version to be more clear, but Google’s style guide and … Read more
