Using Flask and Flask-WTF to build websites in Python 2.7 and 3.6.2 - part 002.

This is one update of my old tutorial about Flask and python 2.7 under Linux from here.
The default install of python 2.7 and pip is very simple - read this tutorial.
First, you need to install the Flask python module under Windows 10:

C:\Python27\Scripts>pip install Flask
Collecting Flask
Downloading Flask-0.11.1-py2.py3-none-any.whl (80kB)
100% |################################| 81kB 564kB/s
Collecting click>=2.0 (from Flask)
Downloading click-6.6-py2.py3-none-any.whl (71kB)
100% |################################| 71kB 1.3MB/s
Collecting Werkzeug>=0.7 (from Flask)
Downloading Werkzeug-0.11.11-py2.py3-none-any.whl (306kB)
100% |################################| 307kB 231kB/s
Collecting Jinja2>=2.4 (from Flask)
Downloading Jinja2-2.8-py2.py3-none-any.whl (263kB)
100% |################################| 266kB 890kB/s
Collecting itsdangerous>=0.21 (from Flask)
Downloading itsdangerous-0.24.tar.gz (46kB)
100% |################################| 51kB 1.3MB/s
Collecting MarkupSafe (from Jinja2>=2.4->Flask)
Downloading MarkupSafe-0.23.tar.gz
Installing collected packages: click, Werkzeug, MarkupSafe, Jinja2, itsdangerous
, Flask
Running setup.py install for MarkupSafe ... done
Running setup.py install for itsdangerous ... done
Successfully installed Flask-0.11.1 Jinja2-2.8 MarkupSafe-0.23 Werkzeug-0.11.11
click-6.6 itsdangerous-0.24

The simple example of the running Flask python module is one script named hello.py:

from flask import Flask
app = Flask(__name__)

@app.route("/")
def hello():
    return "Hello World!"

if __name__ == "__main__":
    app.run()

Using the command to run the script and show the result into your browser:

C:\Python27>python.exe hello.py
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)

Now the installation of Flask-WTF python module:

C:\Python27\Scripts>pip install Flask-WTF
Collecting Flask-WTF
  Downloading Flask_WTF-0.14.2-py2.py3-none-any.whl
Collecting WTForms (from Flask-WTF)
  Downloading WTForms-2.1.zip (553kB)
    100% |################################| 563kB 1.7MB/s
Requirement already satisfied: Flask in c:\python27\lib\site-packages (from Flask-WTF)
Requirement already satisfied: click>=2.0 in c:\python27\lib\site-packages (from Flask->Flask-WTF)
Requirement already satisfied: Werkzeug>=0.7 in c:\python27\lib\site-packages (from Flask->Flask-WTF)
Requirement already satisfied: Jinja2>=2.4 in c:\python27\lib\site-packages (from Flask->Flask-WTF)
Requirement already satisfied: itsdangerous>=0.21 in c:\python27\lib\site-packages (from Flask->Flask-WTF)
Requirement already satisfied: MarkupSafe>=0.23 in c:\python27\lib\site-packages (from Jinja2>=2.4->Flask->Flask-WTF)
Installing collected packages: WTForms, Flask-WTF
  Running setup.py install for WTForms ... done
Successfully installed Flask-WTF-0.14.2 WTForms-2.1

Now I try with Python 3.6.2 with both python modules and works great.

C:\Python362\Scripts>pip3.6.exe install flask
...
Successfully installed Jinja2-2.9.6 MarkupSafe-1.0 Werkzeug-0.12.2 click-6.7 flask-0.12.2 itsdangerous-0.24

C:\Python362\Scripts>Flask-WTF
'Flask-WTF' is not recognized as an internal or external command,
operable program or batch file.

C:\Python362\Scripts>pip3.6.exe install Flask-WTF
...
Successfully installed Flask-WTF-0.14.2 WTForms-2.1

The gtts python module.

This python module named gtts will create an mp3 file from spoken text via the Google TTS (Text-to-Speech) API.
The installation of the gtts python module under Windows 10.

C:\Python27\Scripts>pip install gtts
Collecting gtts
  Downloading gTTS-1.2.0.tar.gz
Requirement already satisfied: six in c:\python27\lib\site-packages (from gtts)
Requirement already satisfied: requests in c:\python27\lib\site-packages (from gtts)
Collecting gtts_token (from gtts)
  Downloading gTTS-token-1.1.1.zip
Requirement already satisfied: chardet<3 .1.0="">=3.0.2 in c:\python27\lib\site-packages (from requests->gtts)
Requirement already satisfied: certifi>=2017.4.17 in c:\python27\lib\site-packages (from requests->gtts)
Requirement already satisfied: idna<2 .6="">=2.5 in c:\python27\lib\site-packages (from requests->gtts)
Collecting urllib3<1 .22="">=1.21.1 (from requests->gtts)
  Using cached urllib3-1.21.1-py2.py3-none-any.whl
Installing collected packages: gtts-token, gtts, urllib3
  Running setup.py install for gtts-token ... done
  Running setup.py install for gtts ... done
  Found existing installation: urllib3 1.22
    Uninstalling urllib3-1.22:
      Successfully uninstalled urllib3-1.22
Successfully installed gtts-1.2.0 gtts-token-1.1.1 urllib3-1.21.1

Let's see a basic example:

from gtts import gTTS
import os
import pygame.mixer
from time import sleep
 
user_text=input("Type your text: ")
 
translate=gTTS(text=user_text ,lang='en')
translate.save('output.wav')

pygame.mixer.init()
path_name=os.path.realpath('output.wav')
real_path=path_name.replace('\\','\\\\')
pygame.mixer.music.load(open(real_path,"rb"))
pygame.mixer.music.play()
while pygame.mixer.music.get_busy():
    sleep(1)

The text will be taken by input into a user_text variable.
You need to type the text into quotes also you will get an error.
The result will be one audio file named output.wav and play it by pygame python module.
This uses the default voices for all languages. I don't find a way to change this voices with python.

Fix Gimp with python script.

Today I will show you how python language can help GIMP users.
From my point of view, Gimp does not properly import frames from GIF files.
This program imports GIF files in this way:

Using the python module, you can get the correct frames from the GIF file.
Here's my script that uses the python PIL module.

import sys
from PIL import Image, ImageSequence
try:
        img = Image.open(sys.argv[1])
except IOError:
        print "Cant load", infile
        sys.exit(1)

pal = img.getpalette()
prev = img.convert('RGBA')
prev_dispose = True
for i, frame in enumerate(ImageSequence.Iterator(img)):
    dispose = frame.dispose

    if frame.tile:
        x0, y0, x1, y1 = frame.tile[0][1]
        if not frame.palette.dirty:
            frame.putpalette(pal)
        frame = frame.crop((x0, y0, x1, y1))
        bbox = (x0, y0, x1, y1)
    else:
        bbox = None

    if dispose is None:
        prev.paste(frame, bbox, frame.convert('RGBA'))
        prev.save('result_%03d.png' % i)
        prev_dispose = False
    else:
        if prev_dispose:
            prev = Image.new('RGBA', img.size, (0, 0, 0, 0))
        out = prev.copy()
        out.paste(frame, bbox, frame.convert('RGBA'))
        out.save('result_%03d.png' % i)

Name the python script with convert_gif.py and then you can use it on the GIF file as follows:

C:\Python27>python.exe convert_gif.py 0001.gif

The final result has a smaller number of images than in Gimp, but this was to be expected.

About py-translate python module.

This python module is used for translating text in the terminal.
You can read and see examples with this API on this web page.
Features

• Fast! Translate an entire book in less than 5 seconds.
• Made for Python 3 but still works on Python 2
• Fast and easy to install, easy to use
• Supports translation from any language
• Highly composable interface, the power of Unix pipes and filters.
• Simple API and documentation

Installation 

C:\>cd Python27

C:\Python27>cd Scripts

C:\Python27\Scripts>pip install py-translate
Collecting py-translate
  Downloading py_translate-1.0.3-py2.py3-none-any.whl (61kB)
    100% |################################| 61kB 376kB/s
Installing collected packages: py-translate
Successfully installed py-translate-1.0.3

C:\Python27\Scripts>

Let's test it with a simple example:

>>> import translate
>>> dir(translate)
['TestLanguages', 'TestTranslator', '__author__', '__build__', '__builtins__', '__copyright__', '__doc__', '__file__', '__license__', '__name__', '__package__', '__path__', '__title__', '__version__', 'accumulator', 'coroutine', 'coroutines', 'languages', 'print_table', 'push_url', 'set_task', 'source', 'spool', 'tests', 'translation_table', 'translator', 'write_stream']
>>> from translate import translator
>>> translator('ro', 'en', 'Consider ca dezvoltarea personala este un pas important')
[[[u'I think personal development is an important step', u'Consider ca dezvoltarea personala este un pas important', None, None, 0]], None, u'ro']
>>>

PyCharm an integrated development environment.

The development team comes with this integrated development environment (I.D.E.) named: PyCharm.
They tell us about this integrated development environment:
Python IDE with a complete set of tools for productive development with Python programming language. In addition, the IDE provides high-class capabilities for professional Web development with Django framework and Google App Engine. It has powerful coding assistance, navigation, a lot of refactoring features, tight integration with various Version Control Systems, Unit testing, powerful all-singing all-dancing Debugger, and entire customization. PyCharm is developer driven IDE. It was developed with the aim of providing you almost everything you need for your comfortable and productive development!
I usually use it and from my point of view, it is very quick to learn and use.
Also, some features like Servers come is supported in the Professional edition only.
The menu is easy to remember and the project settings come automatically.
You can start from the main menu: File - New Project...
A little more complicated element is putting new scripts into the project File - New.
The python file can be added and the type of python version can by editing the configuration menu: Run - Edit Configurations...
The editor comes with unindent and convert fro tabs and spaces.
This I.D.E. comes with common version control operations integrations, like:

• CVS Reference
• Git Reference
• Mercurial Reference
• Perforce Reference
• Subversion Reference

Also, some official tutorials can also be found on the official website.
You can read more about this software here.

The JetBrainsTV is the official youtube channel of this I.D.E.

Python tutor - web tool for python programming.

The website comes with this intro about this web tool.
Python Tutor, created by Philip Guo, helps people overcome a fundamental barrier to learning programming: understanding what happens as the computer runs each line of source code.
Using this tool, you can write Python, Java, JavaScript, TypeScript, Ruby, C, and C++ code in your web browser and visualize what the computer is doing step-by-step as it runs your code.
Over 3.5 million people in over 180 countries have used Python Tutor to visualize over 30 million pieces of code, often as a supplement to textbooks, lectures, and online tutorials.
I tested and worked very well.
You can use python programming language 2.7 and 3.6 versions.
No need to import python modules, you will get an error.
Just programming on the fly to test and see the result.
The website comes with some example to see how to deal with this tool.
Let's see some examples:

example with factorial :

# dumb recursive factorial
def fact(n):
    if (n <= 1):
        return 1
    else:
        return n * fact(n - 1)

print(fact(6))

example with for - else:

# find primes using a for-else construct
for n in range(2, 10):
    x_range = range(2, n)
    for x in x_range:
        if n % x == 0:
            break
    else:
        # loop fell through without finding a factor
        print(n)

example with inputs:

prefix = "Hello "

n1 = raw_input("Enter your name")

n2 = raw_input("Enter another name")

res = prefix + n1 + " and " + n2
print(res)

Run your script just press: Visualize Execution or Live Programming Mode buttons and the will run step by step with:
First, Back, Forward and Last.
One good feature of this tool - with a single line of JavaScript code, you can embed a Python Tutor visualization within any webpage.
Another good feature is COLLABORATE to learn together - this allow us to give and get direction with real-time python programming.
Can be a good tool for python chat users.
Let's show you a screenshot to see how this tool working with python scripting.