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What does the servlet value signify
...on we are having a few servlets defined. Here is the excerpt from the web.xml for one of the servlets:
11 Answers
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Python add item to the tuple
... can do new = a + b instead of new = a + (b,). AFAICT, works the same in python3 and python2.7.
– ILMostro_7
Jun 15 '18 at 11:42
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Accessing items in an collections.OrderedDict by index
...ctions
>>> d = collections.OrderedDict()
>>> d['foo'] = 'python'
>>> d['bar'] = 'spam'
>>> d.items()
[('foo', 'python'), ('bar', 'spam')]
>>> d.items()[0]
('foo', 'python')
>>> d.items()[1]
('bar', 'spam')
Note for Python 3.X
dict.items would ...
Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?
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If you have several versions of Python installed, /usr/bin/env will ensure the interpreter used is the first one on your environment's $PATH. The alternative would be to hardcode something like #!/usr/bin/python; that's ok, but less flexible.
In Unix, an e...
Multiprocessing - Pipe vs Queue
What are the fundamental differences between queues and pipes in Python's multiprocessing package ?
2 Answers
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Django 1.7 - makemigrations not detecting changes
... need to do one pre-step (as I found out) listed in the documentation:
python manage.py makemigrations your_app_label
The documentation does not make it obvious that you need to add the app label to the command, as the first thing it tells you to do is python manage.py makemigrations which wil...
Difference between os.getenv and os.environ.get
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One difference observed (Python27):
os.environ raises an exception if the environmental variable does not exist.
os.getenv does not raise an exception, but returns None
shar...
How do I get the number of elements in a list?
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The len() function can be used with several different types in Python - both built-in types and library types. For example:
>>> len([1,2,3])
3
Official 2.x documentation is here: len()
Official 3.x documentation is here: len()
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Get the first item from an iterable that matches a condition
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In Python 2.6 or newer:
If you want StopIteration to be raised if no matching element is found:
next(x for x in the_iterable if x > 3)
If you want default_value (e.g. None) to be returned instead:
next((x for x in the_it...
Examples of GoF Design Patterns in Java's core libraries
...hich in turn can be used to create another abstract/interface type)
javax.xml.parsers.DocumentBuilderFactory#newInstance()
javax.xml.transform.TransformerFactory#newInstance()
javax.xml.xpath.XPathFactory#newInstance()
Builder (recognizeable by creational methods returning the instance itself)
ja...