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Why is there no tuple comprehension in Python?
... is tuple([generator]).
Performance Comparison
List comprehension:
$ python3 -m timeit "a = [i for i in range(1000)]"
10000 loops, best of 3: 27.4 usec per loop
Tuple from list comprehension:
$ python3 -m timeit "a = tuple([i for i in range(1000)])"
10000 loops, best of 3: 30.2 usec per loop...
List comprehension vs map
...CAN BE LAZY, and in fact is lazy in python. That means you can do this (in python3) and your computer will not run out of memory and lose all your unsaved data:
>>> map(str, range(10**100))
<map object at 0x2201d50>
Try doing that with a list comprehension:
>>> [str(n) fo...
How can I connect to MySQL in Python 3 on Windows?
...as it is a fork
Debian and Ubuntu use it to provide both python-mysqldb andpython3-mysqldb packages.
benchmarks here: https://github.com/methane/mysql-driver-benchmarks
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Print a string as hex bytes?
...
Note that in python3, the concept of printing a str as hex doesn't really make sense; you'll want to print bytes object as hex (convert str to bytes by calling .encode()).
– mic_e
May 8 '15 at 12:53
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How do I parse an ISO 8601-formatted date?
...Traceback (most recent call last):
File "", line 1, in
File "/usr/lib/python3.4/_strptime.py", line 500, in _strptime_datetime
tt, fraction = _strptime(data_string, format)
File "/usr/lib/python3.4/_strptime.py", line 337, in _strptime
(data_string, format))
ValueError: time data '200...
How to get the ASCII value of a character
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@Moustache : In Python3, you'll be using Unicode out-of-the-box.
– tricasse
Oct 1 '19 at 9:33
1
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Class with Object as a parameter
...declares Table to be a new-style class (as opposed to "classic" class).
In Python3 all classes are new-style classes, so this is no longer necessary.
New style classes have a few special attributes that classic classes lack.
class Classic: pass
class NewStyle(object): pass
print(dir(Classic))
# [...
Does uninstalling a package with “pip” also remove the dependent packages?
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Unfortunately it has no real Python3 support, yet (see github.com/invl/pip-autoremove/issues/18) .
– asmaier
Oct 6 '19 at 10:31
10
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How to print to stderr in Python?
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@DanH Yes this forces you to make your code Python3-ready. I guess this could be why many people actually like it!
– MarcH
Nov 18 '14 at 19:00
18
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Changes in import statement python3
...f%2fstackoverflow.com%2fquestions%2f12172791%2fchanges-in-import-statement-python3%23new-answer', 'question_page');
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