The values() method returns a QuerySet containing dictionaries: <QuerySet [{‘comment_id’: 1}, {‘comment_id’: 2}]> The values_list() method returns a QuerySet containing tuples: <QuerySet [(1,), (2,)]> If you are using values_list() with a single field, you can use flat=True to return a QuerySet of single values instead of 1-tuples: <QuerySet [1, 2]>
Solution Since Python 3, input returns a string which you have to explicitly convert to ints, with int, like this x = int(input(“Enter a number: “)) y = int(input(“Enter a number: “)) You can accept numbers of any base and convert them directly to base-10 with the int function, like this >>> data = int(input(“Enter … Read more
You can do it manually with the next command: find . | grep -E “(/__pycache__$|\.pyc$|\.pyo$)” | xargs rm -rf This will remove all .pyc and .pyo files as well as __pycache__ directories recursively starting from the current directory.
You’re mixing different format functions. The old-style % formatting uses % codes for formatting: ‘It will cost $%d dollars.’ % 95 The new-style {} formatting uses {} codes and the .format method ‘It will cost ${0} dollars.’.format(95) Note that with old-style formatting, you have to specify multiple arguments using a tuple: ‘%d days and %d … Read more
As answer by Miles, {% comment %}…{% endcomment %} is used for multi-line comments, but you can also comment out text on the same line like this: {# some text #}
The idea here is to install multiple ipython kernels. Here are instructions for anaconda. If you are not using anaconda, I recently added instructions using pure virtualenvs. Anaconda >= 4.1.0 Since version 4.1.0, anaconda includes a special package nb_conda_kernels that detects conda environments with notebook kernels and automatically registers them. This makes using a new … Read more
Take a look at PEP-238: Changing the Division Operator The // operator will be available to request floor division unambiguously.
TL;DR Making the Right Choice: We have walked through the most popular forms of concurrency. But the question remains – when should choose which one? It really depends on the use cases. From my experience (and reading), I tend to follow this pseudo code: if io_bound: if io_very_slow: print(“Use Asyncio”) else: print(“Use Threads”) else: print(“Multi … Read more
Optional[…] is a shorthand notation for Union[…, None], telling the type checker that either an object of the specific type is required, or None is required. … stands for any valid type hint, including complex compound types or a Union[] of more types. Whenever you have a keyword argument with default value None, you should … Read more
From python 3.2 you can do >>> (1024).to_bytes(2, byteorder=”big”) b’\x04\x00′ https://docs.python.org/3/library/stdtypes.html#int.to_bytes def int_to_bytes(x: int) -> bytes: return x.to_bytes((x.bit_length() + 7) // 8, ‘big’) def int_from_bytes(xbytes: bytes) -> int: return int.from_bytes(xbytes, ‘big’) Accordingly, x == int_from_bytes(int_to_bytes(x)). Note that the above encoding works only for unsigned (non-negative) integers. For signed integers, the bit length is a bit … Read more