Check your version of Werkzeug.  Version 0.10 was just released and numerous changes went into the reloader.  One change is that a default polling reloader is used; the old pyinotify reloader was apparently inaccurate.  If you want more efficient polling, install the [`watchdog`][1] package.  You can see the code related to this [here](https://github.com/mitsuhiko/werkzeug/blob/4e2c6746e565eaba7b3bd7489337580b62db610b/werkzeug/_reloader.py#L246-L251).

When Werkzeug can&#39;t find watchdog, it uses the `stat` reloader, otherwise it uses whatever reloader watchdog uses, which can vary by platform.  This message is just so you know which one is in use.

---

Watchdog may not be compatible with gevent. If you&#39;re using gevent and having issues with the reloader when using Watchdog, check [this GitHub issue](https://github.com/gorakhargosh/watchdog/issues/306).


  [1]: https://pypi.python.org/pypi/watchdog

Use `run(use_reloader=False)` to disable the reloader.

It gave me some problems where it wasn&#39;t able to find my server file when it restarted. This did the trick. It executed just once and everything worked. Quite odd. 

If you run with `app.run(debug=True)`, it will run the reloader as part of debug mode. If you don&#39;t want to use debug mode, pass `debug=False` or don&#39;t pass it at all.

my filename was \_\_main\_\_.py and I exported it as such: export FLASK_APP=\_\_main\_\_.py
Upon changing the name to app.py and reexporting it, it worked.

I am using Moment.js to parse a string and get the day, month and year separately:  

    var date = moment(&quot;12-25-1995&quot;, &quot;MM-DD-YYYY&quot;);
    var day = date.day();        

However, `day` is not 25—it&#39;s 1. What is the correct API method?

.day() returns wrong day of month with Moment.js

This is probably simple and I feel stupid for asking. I want to change the levels of a factor in a data frame, using mutate. Simple example:

    library(&quot;dplyr&quot;)
    dat &lt;- data.frame(x = factor(&quot;A&quot;), y = 1)
    mutate(dat,levels(x) = &quot;B&quot;)

I get:

    Error: Unexpected &#39;=&#39; in &quot;mutate(dat,levels(x) =&quot;

Why is this not working? How can I change factor levels with mutate?

Changing factor levels with dplyr mutate

I&#39;ve built a few Flask apps, but on my latest project I noticed something a little strange in development mode.  The second line of the usual message in the terminal which always reads:

     * Running on http://127.0.0.1:5000/
     * Restarting with reloader

has been replaced by:

     * Restarting with stat

I don&#39;t think I&#39;ve done anything different, in fact, I started by cloning a starter-kit project that I have used many times, which itself, does not display this behavior.  I also notice that this project consumes about 15% CPU steadily, whereas my other project are barely a blip.

Any ideas why this is happening?

Flask app &quot;Restarting with stat&quot;

I've built a few Flask apps, but on my latest project I noticed something a little strange in development mode. The second line of the usual message in the terminal which always reads:
<pre><code class="hljs language-csharp"> * Running on http://127.0.0.1:5000/
 * Restarting with reloader
</code></pre>
has been replaced by:
<pre><code class="hljs language-bash"> * Restarting with stat
</code></pre>
I don't think I've done anything different, in fact, I started by cloning a starter-kit project that I have used many times, which itself, does not display this behavior. I also notice that this project consumes about 15% CPU steadily, whereas my other project are barely a blip.
Any ideas why this is happening?

Im trying to install numpy with PyCharm but i keep getting this error: 

&gt; error: Microsoft Visual C++ 10.0 is required (Unable to find
&gt; vcvarsall.bat).

Can someone please explain to me exactly what i have to do to fix this error(and as simple and detailed as possible)? im using python 3.4.2 (i know this has been answered before but i did not understand it).

Error: Microsoft Visual C++ 10.0 is required (Unable to find vcvarsall.bat) when running Python script

In R (thanks to [magrittr][1]) you can now perform operations with a more functional piping syntax via `%&gt;%`. This means that instead of coding this: 

    &gt; as.Date(&quot;2014-01-01&quot;)
    &gt; as.character((sqrt(12)^2)

You could also do this: 

    &gt; &quot;2014-01-01&quot; %&gt;% as.Date 
    &gt; 12 %&gt;% sqrt %&gt;% .^2 %&gt;% as.character

To me this is more readable and this extends to use cases beyond the dataframe. Does the python language have support for something similar?

[1]: https://magrittr.tidyverse.org/

Functional pipes in python like %&gt;% from R&#39;s magrittr

I am working on Django project with virtualenv and connect it to local postgres database. when i run the project is says,

    ImportError: No module named psycopg2.extensions

then i used this command to install 

    pip install psycopg2


then during the installation it gives following error.

    Downloading/unpacking psycopg2==2.4.4
      Downloading psycopg2-2.4.4.tar.gz (648kB): 648kB downloaded
      Running setup.py (path:/home/muhammadtaqi/Projects/MyProjects/OnlineElectionCampaign/venv/build/psycopg2/setup.py) egg_info for package psycopg2
        
        Error: You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application.
        
        Complete output from command python setup.py egg_info:
        running egg_info
    
    creating pip-egg-info/psycopg2.egg-info
    
    writing pip-egg-info/psycopg2.egg-info/PKG-INFO
    
    writing top-level names to pip-egg-info/psycopg2.egg-info/top_level.txt
    
    writing dependency_links to pip-egg-info/psycopg2.egg-info/dependency_links.txt
    
    writing manifest file &#39;pip-egg-info/psycopg2.egg-info/SOURCES.txt&#39;
    
    warning: manifest_maker: standard file &#39;-c&#39; not found
    
    
    
    Error: You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application.
    
    
    
    ----------------------------------------
    Cleaning up...
    Command python setup.py egg_info failed with error code 1 in /home/muhammadtaqi/Projects/MyProjects/OnlineElectionCampaign/venv/build/psycopg2
    Storing debug log for failure in /home/muhammadtaqi/.pip/pip.log



You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application

Not quite sure why I can&#39;t figure this out.  I&#39;m looking to slice a Pandas dataframe by using index numbers.   I have a list/core index with the index numbers that i do NOT need, shown below

     pandas.core.index.Int64Index

     Int64Index([2340, 4840, 3163, 1597, 491 , 5010, 911 , 3085, 5486, 5475, 1417, 2663, 4204, 156 , 5058, 1990, 3200, 1218, 3280, 793 , 824 , 3625, 1726, 1971, 2845, 4668, 2973, 3039, 376 , 4394, 3749, 1610, 3892, 2527, 324 , 5245, 696 , 1239, 4601, 3219, 5138, 4832, 4762, 1256, 4437, 2475, 3732, 4063, 1193], dtype=int64)

How can I create a new dataframe excluding these index numbers.  I tried 

    df.iloc[combined_index]

and obviously this just shows the rows with those index number (the opposite of what I want). any help will be greatly appreciated

select pandas rows by excluding index number

Let&#39;s assume that I have an XML like this:

&lt;!-- language: lang-xml --&gt;

    &lt;author type=&quot;XXX&quot; language=&quot;EN&quot; gender=&quot;xx&quot; feature=&quot;xx&quot; web=&quot;foobar.com&quot;&gt;
        &lt;documents count=&quot;N&quot;&gt;
            &lt;document KEY=&quot;e95a9a6c790ecb95e46cf15bee517651&quot; web=&quot;www.foo_bar_exmaple.com&quot;&gt;&lt;![CDATA[A large text with lots of strings and punctuations symbols [...]
    ]]&gt;
            &lt;/document&gt;
            &lt;document KEY=&quot;bc360cfbafc39970587547215162f0db&quot; web=&quot;www.foo_bar_exmaple.com&quot;&gt;&lt;![CDATA[A large text with lots of strings and punctuations symbols [...]
    ]]&gt;
            &lt;/document&gt;
            &lt;document KEY=&quot;19e71144c50a8b9160b3f0955e906fce&quot; web=&quot;www.foo_bar_exmaple.com&quot;&gt;&lt;![CDATA[A large text with lots of strings and punctuations symbols [...]
    ]]&gt;
            &lt;/document&gt;
            &lt;document KEY=&quot;21d4af9021a174f61b884606c74d9e42&quot; web=&quot;www.foo_bar_exmaple.com&quot;&gt;&lt;![CDATA[A large text with lots of strings and punctuations symbols [...]
    ]]&gt;
            &lt;/document&gt;
        &lt;/documents&gt;
    &lt;/author&gt;

I would like to read this XML file and convert it to a pandas DataFrame:

&lt;!-- language: lang-shell --&gt;

    key                                         type     language    feature            web                         data
    e95324a9a6c790ecb95e46cf15bE232ee517651      XXX        EN          xx      www.foo_bar_exmaple.com     A large text with lots of strings and punctuations symbols [...]
    bc360cfbafc39970587547215162f0db             XXX        EN          xx      www.foo_bar_exmaple.com     A large text with lots of strings and punctuations symbols [...]
    19e71144c50a8b9160b3cvdf2324f0955e906fce     XXX        EN          xx      www.foo_bar_exmaple.com     A large text with lots of strings and punctuations symbols [...]
    21d4af9021a174f61b8erf284606c74d9e42         XXX        EN          xx      www.foo_bar_exmaple.com     A large text with lots of strings and punctuations symbols [...]

This is what I already tried, but I am getting some errors and probably there is a more efficient way of doing this task:

&lt;!-- language: lang-python --&gt;

    from lxml import objectify
    import pandas as pd
    
    path = &#39;file_path&#39;
    xml = objectify.parse(open(path))
    root = xml.getroot()
    root.getchildren()[0].getchildren()
    df = pd.DataFrame(columns=(&#39;key&#39;,&#39;type&#39;, &#39;language&#39;, &#39;feature&#39;, &#39;web&#39;, &#39;data&#39;))
    
    for i in range(0,len(xml)):
        obj = root.getchildren()[i].getchildren()
        row = dict(zip([&#39;key&#39;,&#39;type&#39;, &#39;language&#39;, &#39;feature&#39;, &#39;web&#39;, &#39;data&#39;], [obj[0].text, obj[1].text]))
        row_s = pd.Series(row)
        row_s.name = i
        df = df.append(row_s)

Could anybody provide me a better aproach for this problem?

How to convert an XML file to nice pandas dataframe?

I started to design a RESTful webservice with Flask and Python and I&#39;m wondering how one would support multiple API versions in the same project.
I&#39;m thinking of putting the requested API version in the URL like this:

&lt;!-- language: lang-none --&gt;

    /myapp/v1/Users

After some time I want to add another endpoint in Version 1.1 of the API and keep everything from v1 which did not change:

&lt;!-- language: lang-none --&gt;

    /myapp/v1.1/Users   &lt;= Same as in v1
    /myapp/v1.1/Books

In v2 the &quot;Users&quot;-endpoint is changed:

&lt;!-- language: lang-none --&gt;

    /myapp/v2/Users   &lt;= Changed in v2
    /myapp/v2/Books   &lt;= Same as in v1.1

and so on...

Looking at [this][1] question the easiest way probably would be something like this:

&lt;!-- language: python --&gt;

    @app.route(&#39;/&lt;version&gt;/users&#39;)
    def users(version):
        # do something
        return jsonify(response)

But I can imagine that this will get harder to maintain with each new API version. Therefore I was wondering if there&#39;s any better (= easier to maintain and better structured) way to achieve this with Flask?

  [1]: https://stackoverflow.com/questions/19085166/what-is-the-best-way-to-run-rest-api-versions-with-python-flask

Support multiple API versions in flask

I have code within a Flask application that uses JSONs in the request, and I can get the JSON object like so:

    Request = request.get_json()

This has been working fine, however I am trying to create unit tests using Python&#39;s unittest module and I&#39;m having difficulty finding a way to send a JSON with the request.

    response=self.app.post(&#39;/test_function&#39;, 
                           data=json.dumps(dict(foo = &#39;bar&#39;)))

This gives me:

    &gt;&gt;&gt; request.get_data()
    &#39;{&quot;foo&quot;: &quot;bar&quot;}&#39;
    &gt;&gt;&gt; request.get_json()
    None

 Flask seems to have a JSON argument where you can set json=dict(foo=&#39;bar&#39;) within the post request, but I don&#39;t know how to do that with the unittest module.

How to send requests with JSON in unit tests

Is there a way to add a global catch-all error handler in which I can change the response to a generic JSON response?

I can&#39;t use the `got_request_exception` signal, as it is not allowed to modify the response (http://flask.pocoo.org/docs/0.10/signals/).
&gt; In contrast all signal handlers are executed in undefined order and do not modify any data.

I would prefer to not wrap the `app.handle_exception` function as that feels like internal API. I guess I&#39;m after something like:

     @app.errorhandler()
     def handle_global_error(e):
         return &quot;Global error&quot;

Note the `errorhandler` does not take any parameters, meaning it would catch all exceptions/status codes which does not have a specific error handler attached to them. I know I can use `errorhandler(500)` or `errorhandler(Exception)` to catch exceptions, but if I do `abort(409)` for example, it will still return a HTML response.

Global error handler for any exception

I am newbie to python and using Python Flask and generating REST API service.

I want to check authorization header which is sent the client.

But I can&#39;t find way to get HTTP header in flask.

Any help for getting HTTP header authorization is appreciated.

How to get http headers in flask?

I am working with flask in a virtual environment. I was able to install matplotlib with pip, and I can `import matplotlib` in a Python session. However, when I import it as 

    matplotlib.pyplot as plt

I get the following error: 

    &gt;&gt;&gt; import matplotlib.pyplot as plt

    Traceback (most recent call last):
      File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
      File &quot;//anaconda/envs/myenv/lib/python2.7/site-packages/matplotlib/pyplot.py&quot;, line 109, in &lt;module&gt;
        _backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
      File &quot;//anaconda/envs/myenv/lib/python2.7/site-packages/matplotlib/backends/__init__.py&quot;, line 32, in pylab_setup
        globals(),locals(),[backend_name],0)
      File &quot;//anaconda/envs/myenv/lib/python2.7/site-packages/matplotlib/backends/backend_macosx.py&quot;, line 24, in &lt;module&gt;
        from matplotlib.backends import _macosx
    RuntimeError: Python is not installed as a framework. The Mac OS X backend will not be able to function correctly if Python is not installed as a framework. See the Python documentation for more information on installing Python as a framework on Mac OS X. Please either reinstall Python as a framework, or try one of the other backends.

I am confused about why it asks me to install Python as framework. Doesn&#39;t it already exists? What does it mean to &quot;install Python as framework&quot;, and how do I install it? 


Content Type	Original Author	Original Content on Stackoverflow
Question	domoarigato	View Question on Stackoverflow
Solution 1 - Python	davidism	View Answer on Stackoverflow
Solution 2 - Python	Cyrus Dsouza	View Answer on Stackoverflow
Solution 3 - Python	NickJason	View Answer on Stackoverflow
Solution 4 - Python	maganoegi	View Answer on Stackoverflow

Flask app "Restarting with stat"

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Solution 4 - Python

Changing factor levels with dplyr mutate

.day() returns wrong day of month with Moment.js

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