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How to run code when a class is subclassed? [duplicate]

...bases, clsdict) where in this case, name equals the string 'Superclass', and bases is the tuple (object, ). The clsdict is a dictionary of the class attributes defined in the body of the class definition. Note the similarity to myclass = type(name, bases, clsdict). So, just as you would use a cl...
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What's the difference between equal?, eql?, ===, and ==?

... You might be familiar with === as an equality operator in Javascript and PHP, but this just not an equality operator in Ruby and has fundamentally different semantics. So what does === do? === is the pattern matching operator! === matches regular expressions === checks range membership === che...
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How to implement a binary tree?

... if val == node.v: return node elif (val < node.v and node.l is not None): self._find(val, node.l) elif (val > node.v and node.r is not None): self._find(val, node.r) def deleteTree(self): # garbage collector will do this for u...
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capturing self strongly in this block is likely to lead to a retain cycle

... __weak MyClass *self_ = self; // that's enough self.loadingDidFinishHandler = ^(NSArray *receivedItems, NSError *error){ if (!error) { [self_ showAlertWithError:error]; } else { self_.items = [NSArray arrayWithArray:receivedItems]; [self_.tableView reloadData]; ...
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When saving, how can you check if a field has changed?

... if you make changes to the object, save it, then makes additional changes and call save() on it AGAIN, it will still work correctly. – philfreo Mar 14 '12 at 22:57 17 ...
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How do I detect whether a Python variable is a function?

I have a variable, x , and I want to know whether it is pointing to a function or not. 25 Answers ...
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ImportError in importing from sklearn: cannot import name check_build

...Mannu Yes; Also for me on jupyter notebook, just restarting (shutting down and click-open again) that ipynb py-kernel worked without restarting all of the jupyter notebook. – Abhimanu Kumar May 2 '18 at 15:01 ...
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Is there a difference between “==” and “is”?

...> b == a True # Make a new copy of list `a` via the slice operator, # and assign it to variable `b` >>> b = a[:] >>> b is a False >>> b == a True In your case, the second test only works because Python caches small integer objects, which is an implementation detail...
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Python module for converting PDF to text [closed]

...n Activestate which uses pypdf but the text generated had no space between and was of no use. 13 Answers ...
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how to change any data type into a string in python

...mystring = repr(myvariable) # '4' This is called "conversion" in python, and is quite common. share | improve this answer | follow | ...