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How to initialize a dict with keys from a list and empty value in Python?
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dict.fromkeys([1, 2, 3, 4])
This is actually a classmethod, so it works for dict-subclasses (like collections.defaultdict) as well. The optional second argument specifies the value to use for the keys (defaults to None.)
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Flask SQLAlchemy query, specify column names
How do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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Real life example, when to use OUTER / CROSS APPLY in SQL
I have been looking at CROSS / OUTER APPLY with a colleague and we're struggling to find real life examples of where to use them.
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Preserve Line Breaks From TextArea When Writing To MySQL
I'm using a textarea to enable users to input comments. However, if the users enters new lines, the new lines don't appear when they are outputted. Is there any way to make the line breaks stay.
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How to capture Curl output to a file?
I have a text document that contains a bunch of URLs in this format:
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7
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Concatenating Files And Insert New Line In Between Files
I have multiple files which I want to concat with cat .
Let's say
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7
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Create a dictionary with list comprehension
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Use a dict comprehension:
{key: value for (key, value) in iterable}
Note: this is for Python 3.x (and 2.7 upwards). Formerly in Python 2.6 and earlier, the dict built-in could receive an iterable of key/value pairs, so you ...
What does cmd /C mean? [closed]
I can understand cmd but not cmd /c . I was trying to invoke a java program from the current for which I use Runtime.getRuntime().exec("cmd /C java helloworld"); There arises my doubt.
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How do I make the return type of a method generic?
Is there a way to make this method generic so I can return a string, bool, int, or double? Right now, it's returning a string, but if it's able find "true" or "false" as the configuration value, I'd like to return a bool for example.
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How can I remove the string “\n” from within a Ruby string?
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You need to use "\n" not '\n' in your gsub. The different quote marks behave differently.
Double quotes " allow character expansion and expression interpolation ie. they let you use escaped control chars like \n to represent t...