I know what **PSR-0** is, and how, why, where to use it. 

I&#39;ve googled for this and looked around stackoverflow related posts, but **could not** find anything. Even on its [official page][1] there&#39;s no such definition.

So, the question is, **what does PSR-0 exactly stand for**?


  [1]: http://www.php-fig.org/psr/psr-0/

What does PSR-0 stand for?

I want to create a csv file, but when I run the code, it returns a blank page and no csv file. I use PHP 5.
I use the following code:

    &lt;?php
        $data = array (&#39;aaa,bbb,ccc,dddd&#39;,
                       &#39;123,456,789&#39;,
                       &#39;&quot;aaa&quot;,&quot;bbb&quot;&#39;);
    
        $fp = fopen(&#39;data.csv&#39;, &#39;w&#39;);
        foreach($data as $line){
                 $val = explode(&quot;,&quot;,$line);
                 fputcsv($fp, $val);
        }
        fclose($fp);
    ?&gt;

Thank you!

Creating csv file with php

This was causing me a bit of grief...

I created a dictionary from a list

    l = [&#39;a&#39;,&#39;b&#39;,&#39;c&#39;]
    d = dict.fromkeys(l, [0,0]) # initializing dictionary with [0,0] as values

    d[&#39;a&#39;] is d[&#39;b&#39;] # returns True

How can I make each value of the dictionary a seperate list?  Is this possible without iterating over all keys and setting them equal to a list?  I&#39;d like to modify one list without changing all the others.

dict.fromkeys all point to same list

This was causing me a bit of grief...
I created a dictionary from a list
<pre><code class="hljs language-ini">l = ['a','b','c']
d = dict.fromkeys(l, [0,0]) # initializing dictionary with [0,0] as values

d['a'] is d['b'] # returns True
</code></pre>
How can I make each value of the dictionary a seperate list? Is this possible without iterating over all keys and setting them equal to a list? I'd like to modify one list without changing all the others.

In python how can you extend a class? For example if I have

color.py

    class Color:
        def __init__(self, color):
            self.color = color
        def getcolor(self):
            return self.color

color_extended.py

    import Color
    
    class Color:
        def getcolor(self):
            return self.color + &quot; extended!&quot;

But this doesn&#39;t work...
I expect that if I work in `color_extended.py`, then when I make a color object and use the `getcolor` function then it will return the object with the string &quot; extended!&quot; in the end. Also it should have gotton the init from the import.

Assume python 3.1

How to extend a class in python?

Working on a python assignment and was curious as to what [:-1] means in the context of the following code: `instructions = f.readline()[:-1]`

Have searched on here on S.O. and on Google but to no avail. Would love an explanation!

What does [:-1] mean/do in python?

I am using Popen to call a shell script that is continuously writing its stdout and stderr to a log file. Is there any way to simultaneously output the log file continuously (to the screen), or alternatively, make the shell script write to both the log file and stdout at the same time?  

I basically want to do something like this in Python:

    cat file 2&gt;&amp;1 | tee -a logfile #&quot;cat file&quot; will be replaced with some script

Again, this pipes stderr/stdout together to tee, which writes it both to stdout and my logfile. 

I know how to write stdout and stderr to a logfile in Python. Where I&#39;m stuck is how to duplicate these back to the screen:

    subprocess.Popen(&quot;cat file&quot;, shell=True, stdout=logfile, stderr=logfile)

Of course, I could just do something like this, but is there any way to do this without tee and shell file descriptor redirection?:

    subprocess.Popen(&quot;cat file 2&gt;&amp;1 | tee -a logfile&quot;, shell=True)



How to write to stdout AND to log file simultaneously with Popen?

The samples at &lt;http://docs.python.org/2/howto/logging.html&gt; use both `warn` and `warning`.

What&#39;s the difference between logging.warn and logging.warning in Python?

While this question doesn&#39;t have any real use in practice, I am curious as to how Python does string interning. I have noticed the following.

    &gt;&gt;&gt; &quot;string&quot; is &quot;string&quot;
    True

This is as I expected.

You can also do this.

    &gt;&gt;&gt; &quot;strin&quot;+&quot;g&quot; is &quot;string&quot;
    True

And that&#39;s pretty clever!

But you can&#39;t do this.

    &gt;&gt;&gt; s1 = &quot;strin&quot;
    &gt;&gt;&gt; s2 = &quot;string&quot;
    &gt;&gt;&gt; s1+&quot;g&quot; is s2
    False

Why wouldn&#39;t Python evaluate `s1+&quot;g&quot;`, and realize it is the same as `s2` and point it to the same address? What is actually going on in that last block to have it return `False`?


dict.fromkeys all point to same list

Python Problem Overview

Python Solutions

Creating csv file with php

What does PSR-0 stand for?

Attributions