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How do I concatenate two lists in Python?
...>>> l1 = [1, 2, 3]
>>> l2 = [4, 5, 6]
>>> joined_list = [*l1, *l2] # unpack both iterables in a list literal
>>> print(joined_list)
[1, 2, 3, 4, 5, 6]
This functionality was defined for Python 3.5 it hasn't been backported to previous versions in the 3.x family...
SQLAlchemy - Getting a list of tables
...the baseclass,
>>> Base = sqlalchemy.ext.declarative.declarative_base()
>>> Base.metadata
MetaData(None)
If you are trying to figure out what tables are present in your database, even among the ones you haven't even told SQLAlchemy about yet, then you can use table reflection. ...
How do I convert this list of dictionaries to a csv file?
...
keys = toCSV[0].keys()
with open('people.csv', 'w', newline='') as output_file:
dict_writer = csv.DictWriter(output_file, keys)
dict_writer.writeheader()
dict_writer.writerows(toCSV)
EDIT: My prior solution doesn't handle the order. As noted by Wilduck, DictWriter is more appropriate...
How can I return two values from a function in Python?
... you can return a tuple or a list and unpack it after the call:
def select_choice():
...
return i, card # or [i, card]
my_i, my_card = select_choice()
On line return i, card i, card means creating a tuple. You can also use parenthesis like return (i, card), but tuples are created by com...
What is the most “pythonic” way to iterate over a list in chunks?
... the recipes section of Python's itertools docs:
from itertools import zip_longest
def grouper(iterable, n, fillvalue=None):
args = [iter(iterable)] * n
return zip_longest(*args, fillvalue=fillvalue)
Example
In pseudocode to keep the example terse.
grouper('ABCDEFG', 3, 'x') --> 'ABC...
The type or namespace name 'Objects' does not exist in the namespace 'System.Data'
...ing code-generation templates. These files will typically be named <edmx_file_name>.tt and <edmx_file_name>.Context.tt and be nested under your edmx file in Solution Explorer. You can select the templates in Solution Explorer and press the Del key to delete them.
Note: In Web Site proj...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
... [^0-9] Any single character that's not a digit
\w [a-zA-Z0-9_] Any word character
\W [^a-zA-Z0-9_] Any non-word character
\s [ \r\t\n\f] Any space character
\S [^ \r\t\n\f] Any non-space character
\n [\n] New line
Example 1: Run as macro
The following...
What’s the best way to check if a file exists in C++? (cross platform)
...turns "true" on non-existent files on network shares: "\\machine\share\this_file_doesnt_exist" => true. Last time I checked was on boost 1.33, use caution...
– rlerallut
Nov 6 '08 at 12:54
...
Find the PID of a process that uses a port on Windows
... or, nestat -aon | findstr 123456
– ROMANIA_engineer
Feb 9 '16 at 14:18
Easy way to achieve this on windows ...
In C, do braces act as a stack frame?
... int big[100000000];
foo(big);
}
bar();
}
gives:
_foobar:
pushl %ebp
movl %esp, %ebp
movl $400000008, %eax
call __alloca
cmpl $0, 8(%ebp)
je L2
leal -400000000(%ebp), %eax
movl %eax, (%esp)
call _foo
L2:
ca...
