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Serializing class instance to JSON
...ps() only knows how to serialize a limited set of object types by default, all built-in types. List here: https://docs.python.org/3.3/library/json.html#encoders-and-decoders
One good solution would be to make your class inherit from JSONEncoder and then implement the JSONEncoder.default() function...
Why dict.get(key) instead of dict[key]?
...
It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
What is the list of possible values for navigator.platform as of today? [closed]
...urate.
The definition
As far as I know there isn't a single public list of all possible `navigator.platform` values, even though the property has been around for quite a bit. To make things worse, the property's definition changed throughout the years. It used to be:
navigator.platform indicates th...
How to JSON serialize sets?
...s.
As shown in the json module docs, this conversion can be done automatically by a JSONEncoder and JSONDecoder, but then you would be giving up some other structure you might need (if you convert sets to a list, then you lose the ability to recover regular lists; if you convert sets to a dictionar...
How to Update Multiple Array Elements in mongodb
...At this moment it is not possible to use the positional operator to update all items in an array. See JIRA http://jira.mongodb.org/browse/SERVER-1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and ...
Creating a blocking Queue in .NET?
...threads reading from the same queue. If the queue reaches a specific size all threads that are filling the queue will be blocked on add until an item is removed from the queue.
...
decorators in the python standard lib (@deprecated specifically)
...r('always', DeprecationWarning) # turn off filter
warnings.warn("Call to deprecated function {}.".format(func.__name__),
category=DeprecationWarning,
stacklevel=2)
warnings.simplefilter('default', DeprecationWarning) # reset filter
...
How do you use the ellipsis slicing syntax in Python?
... item):
... if item is Ellipsis:
... return "Returning all items"
... else:
... return "return %r items" % item
...
>>> x = TestEllipsis()
>>> print x[2]
return 2 items
>>> print x[...]
Returning all items
Of course, there is the ...
Print current call stack from a method in Python code
In Python, how can I print the current call stack from within a method (for debugging purposes).
7 Answers
...
No module named _sqlite3
...opriate .so file. You can correct this problem with the steps below:
Install sqlite-devel (or libsqlite3-dev on some Debian-based systems)
Re-configure and re-compiled Python with ./configure --enable-loadable-sqlite-extensions && make && sudo make install
Note
The sudo make i...