The twill python module with Fedora 25.

Today I tested the twill python module with python 2.7 and Fedora 25.
This is: a scripting system for automating Web browsing. Useful for testing Web pages or grabbing data from password-protected sites automatically.
To install this python module I used pip command:
[root@localhost mythcat]# pip install twill
Collecting twill
Downloading twill-1.8.0.tar.gz (176kB)
100% |████████████████████████████████| 184kB 2.5MB/s
Installing collected packages: twill
Running setup.py install for twill ... done
Successfully installed twill-1.8.0

Let's try some tests:

[mythcat@localhost ~]$ python
Python 2.7.13 (default, Jan 12 2017, 17:59:37) 
[GCC 6.3.1 20161221 (Red Hat 6.3.1-1)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from twill import get_browser
>>> b = get_browser()
>>> 
>>> from twill.commands import *
>>> go("http://www.python.org/")
==> at https://www.python.org/
u'https://www.python.org/'
>>> b.showforms()

Form #1
## ## __Name__________________ __Type___ __ID________ __Value__________________
1     q                        search    id-searc ...   

To talk to the Web browser directly, call the get_browser function.
You can see most of the twill commands by using:

>>> import twill.shell
>>> twill.shell.main()

 -= Welcome to twill! =-

current page: https://www.python.org/widgets
>> ?

Undocumented commands:
======================
add_auth             fa           info             save_html           title
add_extra_header     find         load_cookies     setglobal           url  
agent                follow       notfind          setlocal          
back                 formaction   redirect_error   show              
clear_cookies        formclear    redirect_output  show_cookies      
clear_extra_headers  formfile     reload           show_extra_headers
code                 formvalue    reset_browser    showforms         
config               fv           reset_error      showhistory       
debug                get_browser  reset_output     showlinks         
echo                 getinput     run              sleep             
exit                 getpassword  runfile          submit            
extend_with          go           save_cookies     tidy_ok           

current page: https://www.python.org/widgets
>> 

Basic is used by setlocal to fill website forms and the go function.
Ban can be very good for some tasks.
The twill python module also provides a simple wrapper for mechanizing functionality with the API is still unstable.

Compare two images: the histogram method.

This is a very simple example about how to compare the histograms of both images and print the inconsistencies are bound to arise.
The example come with alternative solution: Histogram method.
The script was run under Fedora 25.
If the images are the same the result will be 0.0.
For testing I change the image2.png by make a line into this with a coverage of 10%.
The result of the script was:
1116.63243729
The images come with this dimensions: 738 x 502 px.

import math
import operator
from math import *
import PIL

from PIL import Image
h1 = Image.open("image1.png").histogram()
h2 = Image.open("image2.png").histogram()

rms = math.sqrt(reduce(operator.add,
        map(lambda a,b: (a-b)**2, h1, h2))/len(h1))
print rms

About the operator module exports a set of efficient functions corresponding to the intrinsic operators of Python.
Example:
operator.lt(a, b)
operator.le(a, b)
operator.eq(a, b)
operator.ne(a, b)
operator.ge(a, b)
operator.gt(a, b)
operator.__lt__(a, b)
operator.__le__(a, b)
operator.__eq__(a, b)
operator.__ne__(a, b)
operator.__ge__(a, b)
operator.__gt__(a, b)
This is like math operators:
lt(a, b) is equivalent to a < b
le(a, b) is equivalent to a <= b
Another example:
>>> # Elementwise multiplication
>>> map(mul, [0, 1, 2, 3], [10, 20, 30, 40])
[0, 20, 60, 120]

>>> # Dot product
>>> sum(map(mul, [0, 1, 2, 3], [10, 20, 30, 40]))
200