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Generate a random letter in Python
Is there a way to generate random letters in Python (like random.randint but for letters)? The range functionality of random.randint would be nice but having a generator that just outputs a random letter would be better than nothing.
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Apache: “AuthType not set!” 500 Error
...d the Apache httpd web server. I'm firing up a local server for a project and when I try to request localhost/index.html, I get a 500 error and I see this in the error log:
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Change multiple files
The following command is correctly changing the contents of 2 files.
9 Answers
9
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Shell - Write variable contents to a file
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Use the echo command:
var="text to append";
destdir=/some/directory/path/filename
if [ -f "$destdir" ]
then
echo "$var" > "$destdir"
fi
The if tests that $destdir represents a file.
The > appends the text after truncating the ...
Create Pandas DataFrame from a string
... to do this is to use StringIO.StringIO (python2) or io.StringIO (python3) and pass that to the pandas.read_csv function. E.g:
import sys
if sys.version_info[0] < 3:
from StringIO import StringIO
else:
from io import StringIO
import pandas as pd
TESTDATA = StringIO("""col1;col2;col3
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How to change a DIV padding without affecting the width/height ?
I have a div that I want to specify a FIXED width and height for, and also a padding which can be changed without decreasing the original DIV width/height or increasing it, is there a CSS trick for that, or an alternative using padding?
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Bash script processing limited number of commands in parallel
...ple, 4 processes process1 ... process4 would be started in the background, and the shell would wait until those are completed before starting the next set.
From the GNU manual:
wait [jobspec or pid ...]
Wait until the child process specified by each process ID pid or job specification jobsp...
Is there a way to break a list into columns?
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If you want a preset number of columns, you can use column-count and column-gap, as mentioned above.
However, if you want a single column with limited height that would break into more columns if needed, this can be achieved quite simply by changing display to flex.
This will not work o...
How to generate keyboard events in Python?
...(1, ctypes.byref(x), ctypes.sizeof(x))
def AltTab():
"""Press Alt+Tab and hold Alt key for 2 seconds
in order to see the overlay.
"""
PressKey(VK_MENU) # Alt
PressKey(VK_TAB) # Tab
ReleaseKey(VK_TAB) # Tab~
time.sleep(2)
ReleaseKey(VK_MENU) # Alt~
if __name__ ...
Syntax for a single-line Bash infinite while loop
I am having trouble coming up with the right combination of semicolons and/or braces. I'd like to do this, but as a one-liner from the command line:
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