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append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
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New features in java 7
What new features in java 7 is going to be implemented?
And what are they doing now?
8 Answers
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Canvas is stretched when using CSS but normal with “width” / “height” properties
I have 2 canvases, one uses HTML attributes width and height to size it, the other uses CSS:
8 Answers
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Git: How to squash all commits on branch
... HEAD))
[That] automatically uses the branch you are currently on.
And if you use that, you can also use an alias, as the command doesn't rely on the branch name.
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Forward declaring an enum in C++
... char or an int, or something else.
From Section 7.2.5 of the ISO C++ Standard:
The underlying type of an enumeration is an integral type that can represent all the enumerator values defined in the enumeration. It is implementation-defined which integral type is used as the underlying type fo...
Why are these numbers not equal?
...umbers can be represented exactly in IEEE floating point arithmetic (the standard that almost all computers use to represent decimal numbers and do math with them), you will not always get what you expected. This is especially true because some values which are simple, finite decimals (such as 0.1 a...
How to duplicate a git repository? (without forking)
I have two repositories, and I need to copy whole of one onto the other empty one which has different access levels from the first one. The copy and the mother repository should not be linked together.
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How to overcome “datetime.datetime not JSON serializable”?
...h requires no dependencies.
As you are using mongoengine (per comments) and pymongo is a dependency, pymongo has built-in utilities to help with json serialization:
http://api.mongodb.org/python/1.10.1/api/bson/json_util.html
Example usage (serialization):
from bson import json_util
import json...
Clang vs GCC for my Linux Development project
I'm in college, and for a project we're using C. We've explored GCC and Clang, and Clang appears to be much more user friendly than GCC. As a result, I'm wondering what the advantages or disadvantages are to using clang, as opposed to GCC, for developing in C and C++ on Linux?
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Can we instantiate an abstract class?
... are creating an instance of an anonymous subclass of your abstract class. And then you are invoking the method on your abstract class reference pointing to subclass object.
This behaviour is clearly listed in JLS - Section # 15.9.1: -
If the class instance creation expression ends in a class b...