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Assignment inside lambda expression in Python
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The assignment expression operator := added in Python 3.8 supports assignment inside of lambda expressions. This operator can only appear within a parenthesized (...), bracketed [...], or braced {...} expression for syntactic reasons. For example, we will be able to write...
How can I check file size in Python?
I am writing a Python script in Windows. I want to do something based on the file size. For example, if the size is greater than 0, I will send an email to somebody, otherwise continue to other things.
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Python: try statement in a single line
Is there a way in python to turn a try/except into a single line?
12 Answers
12
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Circular (or cyclic) imports in Python
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There was a really good discussion on this over at comp.lang.python last year. It answers your question pretty thoroughly.
Imports are pretty straightforward really. Just remember the following:
'import' and 'from xxx import yyy' are executable statements. They execute
when ...
Creating an empty list in Python
What is the best way to create a new empty list in Python?
5 Answers
5
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Finding the index of elements based on a condition using python list comprehension
The following Python code appears to be very long winded when coming from a Matlab background
5 Answers
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Understanding slice notation
I need a good explanation (references are a plus) on Python's slice notation.
33 Answers
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Access nested dictionary items via a list of keys?
... the dictionary:
from functools import reduce # forward compatibility for Python 3
import operator
def getFromDict(dataDict, mapList):
return reduce(operator.getitem, mapList, dataDict)
and reuse getFromDict to find the location to store the value for setInDict():
def setInDict(dataDict, mapL...
Reverse / invert a dictionary mapping
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For Python 2.7.x
inv_map = {v: k for k, v in my_map.iteritems()}
For Python 3+:
inv_map = {v: k for k, v in my_map.items()}
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Multiple constructors in python? [duplicate]
Is it not possible to define multiple constructors in Python, with different signatures? If not, what's the general way of getting around it?
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