Is python code safe after deployment?
How do I protect Python code from being read by users?
is a simple way to script small GUIs.  Can anyone give a nice example with a button and a text widget. When the button is pressed should a shell command be executed and the output piped to the text widget.  If you have other nice and clean examples for useful tasks, please add them too. From time to time I lose all edits because of undo in Object Mode. If I enter immediately after Undo in Edit Mode I can't redo, and switching again in Object results in losing all edit history.  How can I resolve this? Separating undo history by mode or linear/unified will both be acceptable.  Edit:I think the most preferable solution will be to disable/skip edit undos when in object mode through an addon. Activate Field Service Lightning feature in a Salesforce DX scratch org? I am struggling to figure out how to -- or if it's even possible to -- create a DX scratch org with the "Field Service Lightning" (FSL) feature installed. Based on the feature list  I'm guessing the answer is no and I'll just have to wait. But I'm not sure I'm interpreting that source correctly or missing something entirely since I'm just wrapping my head around DX.   Background: we have a production org with FSL installed and active, along with it's accompanying managed packages. I can create sandboxes from it and do development using standard Metadata API tools, but I was hoping to start a new project using DX. But I'm stuck configuring a scratch org with the proper features. Why is it bad to log in as root? I've often come across posts on forums or other websites where you see people joking in such a manner about running/logging in as root as if it's something awful and everyone ought to know about it. However, there isn't much that a search reveals on the matter.   It may be widely known to Linux experts, but I really don't know why. I remember always running as root when I first tried Linux years ago (Redhat and Mandrake) and don't remember running into any problems because of that.   There are actually some distros that have a bright red background with alert signs all over it as wallpaper for the root user (SuSe?). I still use the "Administrator" account for regular use on my Windows installation and haven't ever run into any problems there either. How to count occurrences of one field grouped by values of another? Is there a way of calculating the number of unique text strings in a field in ArcGIS 10.1? I have a number of repeated strings in this field, but would like to calculate the number of unique strings in a field based on groupings from another field.  E.g  - Current table:  Field 1    Field 2    Apple      Green      Apple      Red        Apple      Red Citrus     Yellow Citrus     Green Citrus     Orange Citrus     Orange   Result:  Field 1    Field 2 Apple      2 Citrus     3 ModuleNotFoundError: No module named 'apt_pkg' error I run below command on ubuntu 16.4 :  sudo add-apt-repository ppa:noobslab/apps  of below question:    and get below error:  Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 11, in &lt;module&gt;     from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg' Error in sys.excepthook: Traceback (most recent call last):   File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 63, in apport_excepthook     from apport.fileutils import likely_packaged, get_recent_crashes   File "/usr/lib/python3/dist-packages/apport/__init__.py", line 5, in &lt;module&gt;     from apport.report import Report   File "/usr/lib/python3/dist-packages/apport/report.py", line 30, in &lt;module&gt;     import apport.fileutils   File "/usr/lib/python3/dist-packages/apport/fileutils.py", line 23, in &lt;module&gt;     from apport.packaging_impl import impl as packaging   File "/usr/lib/python3/dist-packages/apport/packaging_impl.py", line 23, in &lt;module&gt;     import apt   File "/usr/lib/python3/dist-packages/apt/__init__.py", line 23, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg'  Original exception was: Traceback (most recent call last):   File "/usr/bin/add-apt-repository", line 11, in &lt;module&gt;     from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler   File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in &lt;module&gt;     import apt_pkg ModuleNotFoundError: No module named 'apt_pkg'   Thanks for help If I remove Minecraft sound files from .minecraft/assets/objects, will Minecraft be unable to play them? In Minecraft, there are a lot of cool sounds. I decided to find there location and move them to my desktop. I have Ubuntu, and if when I remove them from that folder will Minecraft be unable to play them or is it smart enough to figure out that they are gone and download them again. Before minecraft was installed, it had to download the files. I even moved my favorite song (creative 6) from the sounds. The sounds are not labeled and have seemingly random names like b0b12118a97ddd733a50e9382e91a21652568641 and how will I know what to call them that will be recognized without digging through the index if Minecraft fails to download them? Or do I not have to worry because it will download them again upon launch?  Note: Why does it not label them and call them random names? Was mathematics invented or discovered? What would it mean to say that mathematics was invented and how would this be different from saying mathematics was discovered?   Is this even a serious philosophical question or just a meaningless/tautological linguistic ambiguity? Prove $\csc(x)=\sum_{k=-\infty}^{\infty}\frac{(-1)^k}{x+k\pi}$ How to access object attribute given string corresponding to name of that attribute Modern electronics industry has developed very efficient LEDs with nice and fancy colors (“true green” , “cyan”, and “blue”) based in InGaN technology, or similar. Some of these LEDs are specified as having forward voltages of 3.2 to 4.2 V. Here are examples of such LEDs, , or surface-mount .  But the usual MCUs are powered from 3.3 V supply, and the GPIO output is usually at 3.1-3.2 V, which seems to be barely enough to drive these LEDs . How can I use these LEDs as indicators of some signal statuses, or power rail status? Do I need a series resistor R1 here?    If yes, how do I choose its value?  DISCLAIMER: This "question-answer" comes as elaboration of the original question , to address the particular use case of LEDs as logic state indicators. How do I install OpenStack? How can I identify duplicate image files? Over the years, I've accumulated a lot of pictures, across a bunch of different machines.  I think I've mostly kept them in a yyyy/mm/ directory structure, but especially with some of the older pictures, there seem to be a lot of duplicates.  What's the best way to identify the duplicates?  Are there good tools to do this, or am I going to have to write something on my own? Let $A \in {M_n}$ is nonsingular and each eigenvalue of $A$ is either $+1$ or $-1$.Why $A$ is similar to ${A^{ - 1}}$? Multiple Damage Resistance Similar questions to this have been asked, but I wasn't able to find one that answers this specifically.  Say that you have resistance to slashing damage as well as resistance to fire damage (no caveats to nonmagical damage or not).  You are fighting someone who has a flaming greataxe (just an enchanted item) that deals 1d12+STR slashing damage, plus 1d6 fire damage on hit and they hit you.    How do you calculate the damage?   (1d12+1d6+STR)/2 (1d12/2) + (1d6/2) + STR (1d12+STR/2) + (1d6/2) something else? I have a manuscript that is under review in a major journal which is a main result out of a few recent years of my research. When applying for faculty positions, I would like to send the draft as a part of my writing sample. But since the material is not yet published, I am not sure if it is a good idea.  What are the foreseeable disadvantages of sending an article in review to the faculty search committee?  My area is neuroscience / biomedical engineering.  Update: The paper got into a high-profile journal, and I got a job at a different place which did not require a writing sample. How to find the best route through multiple points? I am using postgreSQL, postGIS and pgrouting. Now I am really confused on how am I going to find the shortest path between multiple points.   I know how to find it between two points through dijkstra but I am confused how to accomplish the same result with more than two points.   I have done some research and found this:    But still I did not understand if its the right way and how to install it. How do I calculate my skill modifier? I'm trying to fill out the skills section on my first character, but when I look at the character sheets in the Starter Set as examples of how to make a character, the skills that are circled have higher modifiers than their Dexterity or Strength or whatever should make them.  I've filled out all skills but those. What do I add to the ability modifier to get those numbers?   My abilities are Strength 13, Dexterity 14, Constitution 11, Intelligence 15, Wisdom 8, and Charisma 8. Proficiencies are Arcana, Athletics, History, Investigation and Stealth. My saving throws are Strength and Dexterity.   I just started D&amp;D and have the Player's Handbook, DM's Guide, Monster Manual, and the Starter Set. I've recently set up the compiz cube again, and I was very happy to find that that flickering window glitch is gone! However, the cube reflection and deformation plugins are also gone.  I am running a fresh 12.10 install, and I have every compiz plugin package installed (including compiz-plugins-extra, which supposedly contains everything that compiz-fusion-plugins-extra package used to have), but those two plugins are still missing. I haven't been able to find anyone with the same problem.   Any ideas? (thanks!) Unique and temporary file names in PHP?