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Tag: python

Calling a view from a management command

So I have added a command to manage.py in my django app that basically takes the results from a view and emails them out to specific users. This command will run on a cron schedule – basically this is done as an automated, emailed report. I’ve figured out how to add in the command but I want to ca…

How to find uid of existing python email object

I have been reading through this document. Most of the document is based on finding an email’s uid. From the article: I’m working with a django app called django-mailbox (http://django-mailbox.readthedocs.org/en/latest/index.html) the purpose of which is to consume emails. The app creates a &#8220…

Assign a value to a list of variables using a loop

I can do this in C, but I haven’t come across it in Python. Say I have a few variables: and I have list of values [1, 2, 3, 4] how can I assign the values to the variables with a single loop so I get the following result: Answer While you technically can modify local variables, doing so is

Parsing a JSON string which was loaded from a CSV using Pandas

I am working with CSV files where several of the columns have a simple json object (several key value pairs) while other columns are normal. Here is an example: After using df = pandas.read_csv(‘file.csv’), what’s the most efficient way to parse and split the stats column into additional col…

Scrapy: Passing item between methods

Suppose I have a Bookitem, I need to add information to it in both the parse phase and detail phase Using the code as is would led to undefined item in the detail phase. How can I pass the item to the detail? detail(self,response,item) doesn’t seem to work. Answer There is an argument named meta for Req…

Python Equivalent for bwmorph

I am still coding a fingerprint image preprocessor on Python. I see in MATLAB there is a special function to remove H breaks and spurs: I have searched scikit, OpenCV and others but couldn’t find an equivalent for these two use of bwmorph. Can anybody point me to right direction or do i have to implemen…

Explanation of how nested list comprehension works?

I have no problem understanding this: I thought that was all, but then I found this snippet: Which makes b = [1,2,3,4,5,6]. The problem is I’m having trouble understanding the syntax in [x for xs in a for x in xs], Could anyone explain how it works? Answer Ah, the incomprehensible “nested” c…

glob exclude pattern

I have a directory with a bunch of files inside: eee2314, asd3442 … and eph. I want to exclude all files that start with eph with the glob function. How can I do it? Answer The pattern rules for glob are not regular expressions. Instead, they follow standard Unix path expansion rules. There are only a f…

How to render transparent text with alpha channel in PyGame?

I am using pygame.font.Font.render() to render some text. I’d like the text to be translucent, ie have an alpha value other than 255, so I tried passing a color argument with an alpha value (eg (255, 0, 0, 150)) as the color argument for pygame.font.Font.render() but it didn’t have any effect. I a…