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How do you validate a URL with a regular expression in Python?
I'm building an app on Google App Engine. I'm incredibly new to Python and have been beating my head against the following problem for the past 3 days.
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How can I fill out a Python string with spaces?
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Felix KlingFelix Kling
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How to import classes defined in __init__.py
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'lib/'s parent directory must be in sys.path.
Your 'lib/__init__.py' might look like this:
from . import settings # or just 'import settings' on old Python versions
class Helper(object):
pass
Then the following exampl...
How do you split a list into evenly sized chunks?
I have a list of arbitrary length, and I need to split it up into equal size chunks and operate on it. There are some obvious ways to do this, like keeping a counter and two lists, and when the second list fills up, add it to the first list and empty the second list for the next round of data, but t...
Internet Explorer 9 not rendering table cells properly
My website has always run smoothly with IE8, IE7, FF, Chrome and Safari. Now I'm testing it on IE9 and I'm experiencing a strange problem: in some pages, some tabular data renders incorrectly.
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Handling a colon in an element ID in a CSS selector [duplicate]
... search_form:expression . I need to specify some styling on that element, but that colon looks like the beginning of a pseudo-element to the browser so it gets marked invalid and ignored. Is there anyway to escape the colon or something?
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How to drop columns by name in a data frame
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You should use either indexing or the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column index...
Android Paint: .measureText() vs .getTextBounds()
I'm measuring text using Paint.getTextBounds() , since I'm interested in getting both the height and width of the text to be rendered. However, the actual text rendered is always a bit wider than the .width() of the Rect information filled by getTextBounds() .
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What exactly does += do in python?
...sent. The __iadd__ method of a class can do anything it wants. The list object implements it and uses it to iterate over an iterable object appending each element to itself in the same way that the list's extend method does.
Here's a simple custom class that implements the __iadd__ special method...
Why is a round-trip conversion via a string not safe for a double?
Recently I have had to serialize a double into text, and then get it back. The value seems to not be equivalent:
3 Answers
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