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Get exception description and stack trace which caused an exception, all as a string

... See the traceback module, specifically the format_exc() function. Here. import traceback try: raise ValueError except ValueError: tb = traceback.format_exc() else: tb = "No error" finally: print tb ...
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Absolute vs relative URLs

...ed Jan 5 '10 at 9:33 Daniel VassalloDaniel Vassallo 301k6666 gold badges475475 silver badges424424 bronze badges ...
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Default filter in Django admin

How can I change the default filter choice from 'ALL'? I have a field named as status which has three values: activate , pending and rejected . When I use list_filter in Django admin, the filter is by default set to 'All' but I want to set it to pending by default. ...
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A simple explanation of Naive Bayes Classification

... & part two being the confusion surrounding Training set. In general all of Machine Learning Algorithms need to be trained for supervised learning tasks like classification, prediction etc. or for unsupervised learning tasks like clustering. During the training step, the algorithms are taught...
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python: How do I know what type of exception occurred?

I have a function called by the main program: 15 Answers 15 ...
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What are some (concrete) use-cases for metaclasses?

...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
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How to “perfectly” override a dict?

...or other builtins) directly. It often makes no sense, because what you actually want to do is implement the interface of a dict. And that is exactly what ABCs are for. share | improve this answer ...
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How to list all functions in a Python module?

I have a python module installed on my system and I'd like to be able to see what functions/classes/methods are available in it. ...
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Understanding the difference between __getattr__ and __getattribute__

...oesn't explicitly manage and do that via __getattr__ method. Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it. A classic use case: class A(dict): def __getattr__(self, name): return self[name] a = A()...
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How to select a single field for all documents in a MongoDB collection?

... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents. db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } ) In this example ...