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Don't understand why UnboundLocalError occurs (closure) [duplicate]
What am I doing wrong here?
8 Answers
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How to make an immutable object in Python?
Although I have never needed this, it just struck me that making an immutable object in Python could be slightly tricky. You can't just override __setattr__ , because then you can't even set attributes in the __init__ . Subclassing a tuple is a trick that works:
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How to check if a file exists in Documents folder?
I have an application with In-App Purchase, that when the user buy something, download one html file into the Documents folder of my app.
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How can I default a parameter to Guid.Empty in C#?
I wish to say:
5 Answers
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Why seal a class?
I'd like to hear what is the motivation behind the bulk of sealed classes in the .Net framework. What is the benefit of sealing a class? I cannot fathom how not allowing inheritance can be useful and most likely not the only one fighting these classes.
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What does “hashable” mean in Python?
I tried searching internet but could not find the meaning of hashable.
9 Answers
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FileSystemWatcher vs polling to watch for file changes
I need to setup an application that watches for files being created in a directory, both locally or on a network drive.
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How can I check if an argument is defined when starting/calling a batch file?
I'm trying to use the following validation logic in a batch file but the "usage" block never executes even when no parameter is supplied to the batch file.
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How to unit test an object with database queries
I've heard that unit testing is "totally awesome", "really cool" and "all manner of good things" but 70% or more of my files involve database access (some read and some write) and I'm not sure how to write a unit test for these files.
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List of lists changes reflected across sublists unexpectedly
I needed to create a list of lists in Python, so I typed the following:
14 Answers
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