
What does the "at" (@) symbol do in Python? - Stack Overflow
Jun 17, 2011 · Functions, in Python, are first class objects - which means you can pass a function as an argument to another function, and return functions. Decorators do both of these things. If we stack decorators, the function, as defined, gets passed first to the decorator immediately above it, then the next, and so on.
python - `from ... import` vs `import .` - Stack Overflow
Feb 25, 2012 · It depends on how you want to access the import when you refer to it. from urllib import request # access request directly. mine = request() import urllib.request # used as urllib.request mine = urllib.request()
python - Display a decimal in scientific notation - Stack Overflow
Aug 2, 2011 · As an aside, despite the format % values syntax still being used even within the Python 3 standard library, I believe it's technically deprecated in Python 3, or at least not the recommended formatting method, and the current recommended syntax, starting with Python 2.6, would be '{0:.2E}'.format(Decimal('40800000000.00000000000000')) (or ...
python - How do I pass a variable by reference? - Stack Overflow
Jun 12, 2009 · Python: Python is “pass-by-object-reference”, of which it is often said: “Object references are passed by value.” . Both the caller and the function refer to the same object, but the parameter in the function is a new variable which is …
python - Parse date string and change format - Stack Overflow
Feb 15, 2010 · In python 3.x needs to install python-dateutil pip install python-dateutil – Abhishake Gupta. Commented ...
python - How to concatenate (join) items in a list to a single string ...
Sep 17, 2012 · This function was removed in Python 3 and Python 2 is dead. Even if you are still using Python 2 you should write Python 3 ready code to make the inevitable upgrade easier. Although @Burhan Khalid's answer is good, I think it's more understandable like this:
python - How do I define a function with optional arguments?
A Python function can take in some arguments, take this for example, def add(x,y): return x+ y # calling this will require only x and y add(2,3) # 5 If we want to add as many arguments as we may want, we shall just use *args which shall be a list of more arguments than the number of formal arguments that you previously defined ( x and y ).
python - How do I read from stdin? - Stack Overflow
Sep 20, 2009 · $ python -c "from io import open; open(1,'w').write(open(0).read())" < inputs.txt foo bar baz Addressing other comments and answers One comment suggests ''.join(sys.stdin) for golfing but that's actually longer than sys.stdin.read() - plus Python must create an extra list in memory (that's how str.join works when not given a list) - for contrast:
python - Timeout on a function call - Stack Overflow
Jan 30, 2009 · It was tested with Python 2 and 3. It should also work under Unix/Linux and Windows. First the imports. These attempt to keep the code consistent regardless of the Python version: from __future__ import print_function import sys import threading from time import sleep try: import thread except ImportError: import _thread as thread
How to urlencode a querystring in Python? - Stack Overflow
Apr 9, 2011 · Python 3. In Python 3, the urllib package has been broken into smaller components. You'll use urllib.parse.quote_plus (note the parse child module) import urllib.parse safe_string = urllib.parse.quote_plus(...) Python 2. What you're looking for is urllib.quote_plus: