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Python's equivalent of && (logical-and) in an if-statement
...actually
evaluated because of the print statements:
>>> def print_and_return(value):
... print(value)
... return value
>>> res = print_and_return(False) and print_and_return(True)
False
As you can see only one print statement is executed, so Python really didn't even lo...
Is it possible to make abstract classes in Python?
...
# Python 2
from abc import ABCMeta, abstractmethod
class Abstract:
__metaclass__ = ABCMeta
@abstractmethod
def foo(self):
pass
Whichever way you use, you won't be able to instantiate an abstract class that has abstract methods, but will be able to instantiate a subclass th...
How do I get the full path of the current file's directory?
...3
For the directory of the script being run:
import pathlib
pathlib.Path(__file__).parent.absolute()
For the current working directory:
import pathlib
pathlib.Path().absolute()
Python 2 and 3
For the directory of the script being run:
import os
os.path.dirname(os.path.abspath(__file__))
I...
How can I get a list of all classes within current module in Python?
...
Try this:
import sys
current_module = sys.modules[__name__]
In your context:
import sys, inspect
def print_classes():
for name, obj in inspect.getmembers(sys.modules[__name__]):
if inspect.isclass(obj):
print(obj)
And even b...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
... separate key - the primary (logical) key on the GUID, and the clustering (ordering) key on a separate INT IDENTITY(1,1) column.
As Kimberly Tripp - the Queen of Indexing - and others have stated a great many times - a GUID as the clustering key isn't optimal, since due to its randomness, it will ...
List comprehension with if statement
...
You got the order wrong. The if should be after the for (unless it is in an if-else ternary operator)
[y for y in a if y not in b]
This would work however:
[y if y not in b else other_value for y in a]
...
How do I sort a list by different parameters at different timed
...esult, which is the idea of decending (the opposite of the usual ascending order), while leaving it as zero if they were equal.
– Yishai
Dec 4 '13 at 14:05
5
...
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
...
The output of [6] is in reverse order. name one age 27
– thanos.a
Jan 8 '17 at 21:11
61
...
How do I convert Long to byte[] and back in java
... doing cross-language or cross-platform, then sending the bytes in a known order is important. This method does that (it writes them "high byte first") according to the docs. The accepted answer does not (it writes them in the "current order" according to the docs). The question states that he wa...
How can I generate UUID in C#
...t always reversing. The docs for for Guid.ToByteArray() call out the byte order as little endian, and say the constructor matches. The spec for GUID is little endian. I would think that should be independent of the machine byte order.
– Jeff Walker Code Ranger
...