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Python : List of dict, if exists increment a dict value, if not append a new dict
... a dictionary, this is easy:
# This example should work in any version of Python.
# urls_d will contain URL keys, with counts as values, like: {'http://www.google.fr/' : 1 }
urls_d = {}
for url in list_of_urls:
if not url in urls_d:
urls_d[url] = 1
else:
urls_d[url] += 1
T...
Python class inherits object
... Is there any reason for a class declaration to inherit from object?
In Python 3, apart from compatibility between Python 2 and 3, no reason. In Python 2, many reasons.
Python 2.x story:
In Python 2.x (from 2.2 onwards) there's two styles of classes depending on the presence or absence of ob...
How to avoid “RuntimeError: dictionary changed size during iteration” error?
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In Python 2.x calling keys makes a copy of the key that you can iterate over while modifying the dict:
for i in d.keys():
Note that this doesn't work in Python 3.x because keys returns an iterator instead of a list.
Another ...
“Inner exception” (with traceback) in Python?
My background is in C# and I've just recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python?
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How to read a (static) file from inside a Python package?
Could you tell me how can I read a file that is inside my Python package?
8 Answers
8
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
If I have the following Python code
6 Answers
6
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Alternative for PHP_excel
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I wrote a very simple class for exporting to "Excel XML" aka SpreadsheetML. It's not quite as convenient for the end user as XSLX (depending on file extension and Excel version, they may get a warning message), but it's a lot easier to work with than XLS or XLSX.
http://gith...
How do I implement interfaces in python?
How do I implement Python equivalent of this C# code ?
7 Answers
7
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How to rename a file using Python
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As of Python 3.4 one can use the pathlib module to solve this.
If you happen to be on an older version, you can use the backported version found here
Let's assume you are not in the root path (just to add a bit of difficulty to i...
How often does python flush to a file?
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For file operations, Python uses the operating system's default buffering unless you configure it do otherwise. You can specify a buffer size, unbuffered, or line buffered.
For example, the open function takes a buffer size argument.
http://do...
