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How to get first element in a list of tuples?
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do you mean something like this?
new_list = [ seq[0] for seq in yourlist ]
What you actually have is a list of tuple objects, not a list of sets (as your original question implied). If it is actually a list of sets, then there is no first element because set...
Purpose of Django setting ‘SECRET_KEY’
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Why didn't they call it a salt then? ;)
– datenwolf
Jun 15 '13 at 18:00
30
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How to add new column to MYSQL table?
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Thanks, It worked with - mysql_query("ALTER TABLE assessment ADD q6 INT(1) NOT NULL AFTER q5");
– Steven Trainor
Apr 19 '13 at 21:33
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Partial Commits with Subversion
...sing the full GIT feature set (including partial commits) and then push it all back to the SVN repository.
git-svn (1)
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How to check if a file is a valid image file?
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That won't be sufficient if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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Preventing console window from closing on Visual Studio C/C++ Console application
... (15.9.4) there is an option:
Tools->Options->Debugging->Automatically close the console
The corresponding fragment from the Visual Studio documentation:
Automatically close the console when debugging stops:
Tells Visual Studio to close the console at the end of a debugging session.
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What is the difference between “ is None ” and “ ==None ”
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class Foo:
def __eq__(self,other):
return True
foo=Foo()
print(foo==None)
# True
print(foo is None)
# False
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PHP global in functions
...ngletons, registries, constants). You do not want to use them. A function call should not have to rely on anything outside, e.g.
function fn()
{
global $foo; // never ever use that
$a = SOME_CONSTANT // do not use that
$b = Foo::SOME_CONSTANT; // do not use that unl...
Automatically add all files in a folder to a target using CMake?
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An alternative to manually re-running cmake is to touch the CMakeLists.txt file before running make.
– Seamus Connor
Oct 1 '15 at 16:38
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
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