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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 ...
How can I return pivot table output in MySQL?
...ot-Tables-with-MySQL
http://datacharmer.org/downloads/pivot_tables_mysql_5.pdf
https://codingsight.com/pivot-tables-in-mysql/
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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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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...
Understanding slice notation
I need a good explanation (references are a plus) on Python's slice notation.
33 Answers
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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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How do I keep two side-by-side divs the same height?
...'t say I've ever tested in that :) Good to know though, cheers. (Given its PDF focus I bet it supports some of the print-related features of CSS 2.1 that aren't implemented very well in browsers.)
– Paul D. Waite
Feb 19 '13 at 17:02
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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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How to find if directory exists in Python
In the os module in Python, is there a way to find if a directory exists, something like:
13 Answers
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Python argparse: Make at least one argument required
I've been using argparse for a Python program that can -process , -upload or both:
11 Answers
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