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Reading a huge .csv file
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You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
Resumable downloads when using PHP to send the file?
...e first thing you need to do is to send the Accept-Ranges: bytes header in all responses, to tell the client that you support partial content. Then, if request with a Range: bytes=x-y header is received (with x and y being numbers) you parse the range the client is requesting, open the file as usua...
What is the purpose of python's inner classes?
...dden from the outside world.
More readable, maintainable code: Nesting small classes within top-level classes places the code closer to where it is used.
The main advantage is organization. Anything that can be accomplished with inner classes can be accomplished without them.
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python generator “send” function purpose?
...t's useful, one of the best use cases I've seen is Twisted's @defer.inlineCallbacks. Essentially it allows you to write a function like this:
@defer.inlineCallbacks
def doStuff():
result = yield takesTwoSeconds()
nextResult = yield takesTenSeconds(result * 10)
defer.returnValue(nextResu...
RE error: illegal byte sequence on Mac OS X
...t a valid UTF-8 char.
Note that, by contrast, GNU sed (Linux, but also installable on macOS) simply passes the invalid byte through, without reporting an error.
Using the formerly accepted answer is an option if you don't mind losing support for your true locale (if you're on a US system and you ne...
Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
How to reverse a string in Go?
...size of the input in bytes. It does not correspond to its length. - Not all utf8's runes are of the same size. It can be either 1, 2, 4, or 8. - You should use unicode/ut8 package's method RuneCountInString to get the length of the rune.
– Anvesh Checka
M...
How to output a multiline string in Bash?
How can I output a multipline string in Bash without using multiple echo calls like so:
7 Answers
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How can I dynamically create derived classes from a base class
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This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they are mandatory...
Get the client IP address using PHP [duplicate]
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I usually don't like nested ternaries, but I really like it in this case...
– Charles Harmon
Jul 18 '14 at 20:49
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