I must emphasize on PyCharm Community Edition which does not have any Django integration (v2016.3.2 at question time). I’ve Googled my problem and (surprisingly,) I did not get any answers, (of course I don’t exclude the possibility that there might be some, be but I just missed them). The questio…
How to write a generator class?
I see lot of examples of generator functions, but I want to know how to write generators for classes. Lets say, I wanted to write Fibonacci series as a class. Output: Why is the value self.a not getting printed? Also, how do I write unittest for generators? Answer How to write a generator class? You’re …
Why when I extend a list does it have ‘NoneType’ as type?
I am looking to extend a list and have the following This gives ListC as having <type ‘NoneType’> and I am wondering why this isn’t just a list as well. Thanks! Answer extend, like many other list operations, operates in-place and returns None. ListA is modified with the extra elements…
How to tell if Python module is a namespace module
In Python 3, modules can be namespace modules without an __init__.py (as per PEP 420) or as a regular module (i.e. ‘[modules] packages as they are implemented in Python 3.2 and earlier’ – PEP 420) that have an __init__.py or are a single .py file. How can you tell the difference between a na…
Optional[Type[Foo]] raises TypeError in Python 3.5.2
This code: will raise TypeError on 3.5.2: whereas it runs fine on 3.6. Same problem if I spell out Optional as Union[None, Type[Foo]]. Is there any workaround for 3.5.2, while still accurately annotating the return type? Answer This is a bug in Python 3.5.2. Optional[cls] is a wrapper for Union[cls, type(None…
Trying to ignore Nan in csv file throws a typeerror
I’m loading a local csv file that contains data. I’m trying to find the smallest float in a row thats mixed of NaN and numbers. I have tried using the numpy function called np.nanmin, but it throws: Any suggestions to why nanmin might not work? A link to the entire csv file: http://www.sharecsv.co…
How to parse xml from local file or url with lxml?
I try to use lxml to parse xml, but I have a problem: Here is my code: I’m a newbie on lxml. Please help me to fix this issue. There is my xml content One more, could we have parse xml from url with lxml. Thanks & Best Regards, Answer The reason you are getting the error message invalid x
Parse human-readable filesizes into bytes
I want to convert all this strings into bytes. So far I came up with this: But I don’t like it and also I don’t think it works. I could find only modules that do the opposite thing. Answer Here’s a slightly prettier version. There’s probably no module for this, just define the function…
python: codingbat no_teen_sum – why my function isn’t working as expected?
Below is the code I used for the no_teen_sum and subsequent fixed_teen functions. The first code is what I submitted – and worked for all test cases: And the fix_teen function that is called: However, looking at this I saw a lot of repitition and realized maybe I had misread what the question was asking…
Make largest palindrome by changing at most K-digits from given numerical string using python?
Make largest palindrome by changing at most K-digits from the given numerical string using the python programming. Answer “Hello, ALL..This program help you to make the numerical string as largest palindrome with ‘k’number of changes !” !/usr/bin/python I’ve used list instead of …