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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
...
List attributes of an object
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>>> class new_class():
... def __init__(self, number):
... self.multi = int(number) * 2
... self.str = str(number)
...
>>> a = new_class(2)
>>> a.__dict__
{'multi': 4, 'str': '2'}
>>> a.__dict__.keys(...
Difference between __str__ and __repr__?
What is the difference between __str__ and __repr__ in Python?
23 Answers
23
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A python class that acts like dict
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class Mapping(dict):
def __setitem__(self, key, item):
self.__dict__[key] = item
def __getitem__(self, key):
return self.__dict__[key]
def __repr__(self):
return repr(self.__dict__)
def __len__(self):
re...
xtree(1796): warning C4800: “int”: 将值强制为布尔值“true”或“false...
...e\xtree(1775): 参见对正在编译的函数 模板 实例化“std::pair<_Ty1,_Ty2> std::_Tree<_Traits>::_Insert_nohint<std::pair<const _Kty,_Ty>&,_Nodety>(bool,_Valty,_Nodety)”的引用
1> with
1> [
1> _Ty1=std::_Tree_iterator<std::_Tree_val<std::_Tree_simple_t...
What is a Question Mark “?” and Colon “:” Operator Used for? [duplicate]
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To me, your answer was the only one that made sense based on how you laid it out. So thank you and I have republished your answer with a citation. garrett.ms/2019/07/24/…
– Cody
Jul 24 '19 at 19:20
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How to print instances of a class using print()?
...
>>> class Test:
... def __repr__(self):
... return "Test()"
... def __str__(self):
... return "member of Test"
...
>>> t = Test()
>>> t
Test()
>>> print(t)
member of Test
The __str__ method is what h...
Python __str__ and lists
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Calling string on a python list calls the __repr__ method on each element inside. For some items, __str__ and __repr__ are the same. If you want that behavior, do:
def __str__(self):
...
def __repr__(self):
return self.__str__()
...
What is the __del__ method, How to call it?
I am reading a code. There is a class in which __del__ method is defined. I figured out that this method is used to destroy an instance of the class. However, I cannot find a place where this method is used. The main reason for that is that I do not know how this method is used, probably not like ...
Relative imports in Python 2.7
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Naming
When a file is loaded, it is given a name (which is stored in its __name__ attribute). If it was loaded as the top-level script, its name is __main__. If it was loaded as a module, its name is the filename, preceded by the names of any packages/subpackages of which it is a part, separated...