For a more general solution that works regardless of the number of dimensions, use `copy.deepcopy()`:

    import copy
    b = copy.deepcopy(a)

I&#39;m using Python 2.6 and cx_Freeze 4.1.2 on a Windows system. I&#39;ve created the setup.py to build my executable and everything works fine.

When cx_Freeze runs, it moves everything to the `build` directory. I have some other files that I would like included in my `build` directory. How can I do this? Here&#39;s my structure:

    src\
        setup.py
        janitor.py
        README.txt
        CHNAGELOG.txt
        helpers\
            uncompress\
                unRAR.exe
                unzip.exe

Here&#39;s my snippet:

&gt;  setup
&gt;      
&gt;     ( name=&#39;Janitor&#39;,
&gt;       version=&#39;1.0&#39;,
&gt;       description=&#39;Janitor&#39;,
&gt;       author=&#39;John Doe&#39;,
&gt;       author_email=&#39;john.doe@gmail.com&#39;,
&gt;       url=&#39;http://www.this-page-intentionally-left-blank.org/&#39;,
&gt;       data_files = 
&gt;           [ (&#39;helpers\uncompress&#39;, [&#39;helpers\uncompress\unzip.exe&#39;]),
&gt;             (&#39;helpers\uncompress&#39;, [&#39;helpers\uncompress\unRAR.exe&#39;]),
&gt;             (&#39;&#39;, [&#39;README.txt&#39;])
&gt;           ],
&gt;       executables =
&gt;           [
&gt;           Executable\
&gt;               (
&gt;               &#39;janitor.py&#39;, #initScript
&gt;               )
&gt;           ]
&gt;     )


I can&#39;t seem to get this to work. Do I need a `MANIFEST.in` file?

How can I bundle other files when using cx_freeze?

I use the following DataGrid

    &lt;DataGrid Grid.Row=&quot;1&quot; Grid.Column=&quot;1&quot; Name=&quot;Grid&quot; ItemsSource=&quot;{Binding}&quot;  AutoGenerateColumns=&quot;False&quot; &gt;
                &lt;DataGrid.Columns&gt;
                    &lt;DataGridTextColumn Header=&quot;Name&quot; Width=&quot;100&quot; Binding=&quot;{Binding Path=Name}&quot;&gt;&lt;/DataGridTextColumn&gt;
                    &lt;DataGridTextColumn Header=&quot;OldValue&quot; Width=&quot;100&quot; Binding=&quot;{Binding Path=OldValue}&quot;&gt;&lt;/DataGridTextColumn&gt;
                    &lt;DataGridTextColumn Header=&quot;NewValue&quot; Width=&quot;100*&quot; Binding=&quot;{Binding Path=NewValue}&quot;&gt;&lt;/DataGridTextColumn&gt;
                &lt;/DataGrid.Columns&gt;
            &lt;/DataGrid&gt;

How can I make the cells readonly?

WPF DataGrid: Make cells readonly

I want to copy a 2D list, so that if I modify one list, the other is not modified.

For a one-dimensional list, I just do this:

    a = [1, 2]
    b = a[:]

And now if I modify `b`, `a` is not modified.

But this doesn&#39;t work for a two-dimensional list:

    a = [[1, 2],[3, 4]]
    b = a[:]

If I modify `b`, `a` gets modified as well.

How do I fix this?

Copying nested lists in Python

I want to copy a 2D list, so that if I modify one list, the other is not modified.
For a one-dimensional list, I just do this:
<pre><code class="hljs language-css">a = [1, 2]
b = a[:]
</code></pre>
And now if I modify <code>b</code>, <code>a</code> is not modified.
But this doesn't work for a two-dimensional list:
<pre><code class="hljs language-css">a = [[1, 2],[3, 4]]
b = a[:]
</code></pre>
If I modify <code>b</code>, <code>a</code> gets modified as well.
How do I fix this?

I want to get an object from the database if it already exists (based on provided parameters) or create it if it does not.

Django&#39;s [`get_or_create`](https://docs.djangoproject.com/en/1.10/ref/models/querysets/#get-or-create) (or [source](https://github.com/django/django/blob/master/django/db/models/query.py#L462)) does this.  Is there an equivalent shortcut in SQLAlchemy?

I&#39;m currently writing it out explicitly like this:

    def get_or_create_instrument(session, serial_number):
        instrument = session.query(Instrument).filter_by(serial_number=serial_number).first()
        if instrument:
            return instrument
        else:
            instrument = Instrument(serial_number)
            session.add(instrument)
            return instrument

Does SQLAlchemy have an equivalent of Django&#39;s get_or_create?

Is there official documentation on the Python website somewhere, on how to install and run multiple versions of Python on the same machine on Linux?

I can find gazillions of blog posts and answers, but I want to know if there is a &quot;standard&quot; official way of doing this?

Or is this all dependent on OS?

Multiple Python versions on the same machine?

I execute an INSERT INTO statement

    cursor.execute(&quot;INSERT INTO mytable(height) VALUES(%s)&quot;,(height))

and I want to get the primary key.

My table has 2 columns: 

    id      primary, auto increment
    height  this is the other column.

How do I get the &quot;id&quot;, after I just inserted this? 

How do I get the &quot;id&quot; after INSERT into MySQL database with Python?

Is there a way to map a signal number (e.g. signal.SIGINT) to its respective name (i.e. &quot;SIGINT&quot;)?

I&#39;d like to be able to print the name of a signal in the log when I receive it, however I cannot find a map from signal numbers to names in Python, i.e.:
    
    import signal
    def signal_handler(signum, frame):
        logging.debug(&quot;Received signal (%s)&quot; % sig_names[signum])

    signal.signal(signal.SIGINT, signal_handler)

For some dictionary sig_names, so when the process receives SIGINT it prints:

    Received signal (SIGINT)

Get signal names from numbers in Python

I would like to be able to get the name of a variable as a string but I don&#39;t know if Python has that much introspection capabilities. Something like:

    &gt;&gt;&gt; print(my_var.__name__)
    &#39;my_var&#39;

I want to do that because I have a bunch of variables I&#39;d like to turn into a dictionary like :

    bar = True
    foo = False
    &gt;&gt;&gt; my_dict = dict(bar=bar, foo=foo)
    &gt;&gt;&gt; print my_dict 
    {&#39;foo&#39;: False, &#39;bar&#39;: True}

But I&#39;d like something more automatic than that.

Python have `locals()` and `vars()`, so I guess there is a way.

Simpler way to create dictionary of separate variables?

    a=[&#39;123&#39;,&#39;2&#39;,4]
    b=a[4] or &#39;sss&#39;
    print b

I want to get a default value when the list index is out of range (here: `&#39;sss&#39;`).

How can I do this?

Getting a default value on index out of range in Python

I have to search through a list and replace all occurrences of one element with another. So far my attempts in code are getting me nowhere, what is the best way to do this?

For example, suppose my list has the following integers

    &gt;&gt;&gt; a = [1,2,3,4,5,1,2,3,4,5,1]

and I need to replace all occurrences of the number 1 with the value 10 so the output I need is 

    &gt;&gt;&gt; a = [10, 2, 3, 4, 5, 10, 2, 3, 4, 5, 10]

Thus my goal is to replace all instances of the number 1 with the number 10.

Finding and replacing elements in a list

I want to sort a list of strings based on the string length. I tried to use sort as follows, but it doesn&#39;t seem to give me correct result.

    xs = [&#39;dddd&#39;,&#39;a&#39;,&#39;bb&#39;,&#39;ccc&#39;]
    print xs
    xs.sort(lambda x,y: len(x) &lt; len(y))
    print xs
    
    [&#39;dddd&#39;, &#39;a&#39;, &#39;bb&#39;, &#39;ccc&#39;]
    [&#39;dddd&#39;, &#39;a&#39;, &#39;bb&#39;, &#39;ccc&#39;]

What might be wrong?

Sorting Python list based on the length of the string

Given an item, how do I count its occurrences in a list in Python?

How do I count the occurrences of a list item?

How do I convert an array to a list in Java?

I used the `Arrays.asList()` but the behavior (and signature) somehow changed from Java SE [1.4.2][1] (docs now in archive) to [8][2] and most snippets I found on the web use the 1.4.2 behaviour.

For example:

    int[] numbers = new int[] { 1, 2, 3 };
    Arrays.asList(numbers)

* on 1.4.2 returns a list containing the elements 1, 2, 3
* on 1.5.0+ returns a list containing the array &#39;numbers&#39;

In many cases it should be easy to detect, but sometimes it can slip unnoticed:

    Assert.assertTrue(Arrays.asList(numbers).indexOf(4) == -1);


  [1]: http://www.oracle.com/technetwork/java/javasebusiness/downloads/java-archive-downloads-142docs-2045554.html
  [2]: https://docs.oracle.com/javase/8/docs/api/java/util/Arrays.html#asList-T...-

Converting array to list in Java

While using `new_list = my_list`, any modifications to `new_list` changes `my_list` every time. Why is this, and how can I clone or copy the list to prevent it?

How do I clone a list so that it doesn&#39;t change unexpectedly after assignment?

How do I copy all files in a directory from another branch? I can list all of the files in that directory by doing 

    git ls-tree master:dirname

I can then copy all of the files individually by doing

    git checkout master -- dirname/filename

However, using wildcards has so far been a total fail.  This does nothing: 

    git checkout master -- dirname/*.png

 Though I guess I can use a bash script to do that, there has to be an easier way, right?

Git: copy all files in a directory from another branch

Why must a copy constructor&#39;s parameter be passed by reference?

Why should the copy constructor accept its parameter by reference in C++?

    $from = &quot;\\something\1 XLS\2010_04_22\*&quot;
    $to =  &quot;c:\out\1 XLS\2010_04_22\&quot;
    copy-item $from $to -Recurse 

This works if `c:\out\1 XLS\2010_04_22\` does exist . Is it possible with a single command to create `c:\out\1 XLS\2010_04_22\` if it doesn&#39;t exist?


Powershell 2 copy-item which creates a folder if doesn&#39;t exist

How to copy all the files present in one directory to another directory using Python.
I have the source path and the destination path as string.

Copy multiple files in Python

I&#39;ll admit that I&#39;m a bit of a ruby newbie (writing rake scripts, now). In most languages, copy constructors are easy to find. Half an hour of searching didn&#39;t find it in ruby. I want to create a copy of the hash so that I can modify it without affecting the original instance. 

Some expected methods that don&#39;t work as intended:

    h0 = {	&quot;John&quot;=&gt;&quot;Adams&quot;,&quot;Thomas&quot;=&gt;&quot;Jefferson&quot;,&quot;Johny&quot;=&gt;&quot;Appleseed&quot;}
    h1=Hash.new(h0)
    h2=h1.to_hash

In the meantime, I&#39;ve resorted to this inelegant workaround

    def copyhash(inputhash)
      h = Hash.new
      inputhash.each do |pair|
        h.store(pair[0], pair[1])
      end
      return h
    end

How do I copy a hash in Ruby?

&gt; **Possible Duplicate:**  
&gt; [How to clone ArrayList and also clone its contents?](https://stackoverflow.com/questions/715650/how-to-clone-arraylist-and-also-clone-its-contents)  

&lt;!-- End of automatically inserted text --&gt;

trying to make a copy of an ArrayList. The underlying object is simple containing on Strings, ints, BigDecimals, Dates and DateTime object.
How can I ensure that the modifications made to new ArrayList are not reflected in the old ArrayList?

    Person morts = new Person(&quot;whateva&quot;);
    			
    List&lt;Person&gt; oldList = new ArrayList&lt;Person&gt;();
    oldList.add(morts);
    oldList.get(0).setName(&quot;Mortimer&quot;);
    
    List&lt;Person&gt; newList = new ArrayList&lt;Person&gt;();
    newList.addAll(oldList);
    
    newList.get(0).setName(&quot;Rupert&quot;);
    
    System.out.println(&quot;oldName : &quot; + oldList.get(0).getName());
    System.out.println(&quot;newName : &quot; + newList.get(0).getName());



Cheers,
P

How to make a deep copy of Java ArrayList

I did some searching found some different methods and posts about creating a deep copy operator.

Is there a quick and easy (built-in) way to deep copy objects in Ruby? The fields are not arrays or hashes.

Working in Ruby 1.9.2.

How to create a deep copy of an object in Ruby?

I wonder whether copying a vector&lt;int&gt; I am copying the vector with its values (whereas this is not working with array, and deep copy need a loop or memcpy).

Could you hint to an explanation?

Regards 

std vector C++ -- deep or shallow copy

In the following piece of code, 


    using System;
    using System.Collections.Generic;
    using System.Drawing;
    using System.Windows.Forms;
    
    namespace clone_test_01
    {
    
    	public partial class MainForm : Form
    	{
    		
    		public class Book
    		{
    			public string title = &quot;&quot;;
    				
    			public Book(string title)
    			{
    				this.title = title;
    			}
    		}
    		
    		
    		public MainForm()
    		{
    			InitializeComponent();
    			
    			List&lt;Book&gt; books_1 = new List&lt;Book&gt;();
    			books_1.Add(  new Book(&quot;One&quot;)  );
    			books_1.Add(  new Book(&quot;Two&quot;)  );
    			books_1.Add(  new Book(&quot;Three&quot;)  );
    			books_1.Add(  new Book(&quot;Four&quot;)  );
    			
    			List&lt;Book&gt; books_2 = new List&lt;Book&gt;(books_1);
    			
    			books_2[0].title = &quot;Five&quot;;
    			books_2[1].title = &quot;Six&quot;;
    			
    			textBox1.Text = books_1[0].title;
    			textBox2.Text = books_1[1].title;
    		}
    	}
    	
    }

I use a `Book` object type to create a `List&lt;T&gt;` and I populate it with a few items giving them a unique title (from &#39;one&#39; to &#39;five&#39;).

Then I create `List&lt;Book&gt; books_2 = new List&lt;Book&gt;(books_1)`. 

From this point, I know it&#39;s a clone of the list object, BUT the book objects from `book_2` are still a reference from the book objects in `books_1`. It&#39;s proven by making changes on the two first elements of `books_2`, and then checking those same elements of `book_1` in a `TextBox`.

`books_1[0].title and books_2[1].title` have indeed been changed to the new values of `books_2[0].title and books_2[1].title`.

**NOW THE QUESTION**

How do we create a new hard copy of a `List&lt;T&gt;`? The idea is that `books_1` and `books_2` become completely independent of each other.

I&#39;m disappointed Microsoft didn&#39;t offer a neat, fast and easy solution like Ruby are doing with the `clone()` method.

What would be really awesome from helpers is to use my code and alter it with a workable solution so it can be compiled and work. I think it will truly help newbies trying to understand offered solutions for this issue.

EDIT: Note that the `Book` class could be more complex and have more properties. I tried to keep things simple.


Content Type	Original Author	Original Content on Stackoverflow
Question	SuperString	View Question on Stackoverflow
Solution 1 - Python	Ayman Hourieh	View Answer on Stackoverflow
Solution 2 - Python	Ignacio Vazquez-Abrams	View Answer on Stackoverflow

Copying nested lists in Python

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

WPF DataGrid: Make cells readonly

How can I bundle other files when using cx_freeze?

Attributions