# Article encoding
encoding = "utf8"
+# You can customize the captcha engine by providing a Captcha class with this
+# interface:
+# Constructor:
+# Captcha(article) -> constructor, takes an article[1] as argument
+# Attributes:
+# puzzle -> a string with the puzzle the user must solve to prove he is
+# not a bot (can be raw HTML)
+# help -> a string with extra instructions, shown only when the user
+# failed to solve the puzzle
+# Methods:
+# validate(form_data) -> based on the form data[2], returns True if
+# the user has solved the puzzle uccessfully
+# (False otherwise).
+#
+# Note you must ensure that the puzzle attribute and validate() method can
+# "communicate" because they are executed in different requests. You can pass a
+# cookie or just calculate the answer based on the article's data, for example.
+#
+# Example: a captcha class to completely disable the captcha feature
+# class Captcha (object):
+# def __init__(self, article):
+# self.puzzle = ''
+# self.help = ''
+# def validate(form_data):
+# return True
+# Remove the captcha input field from the form template, and that's it!
+#
+# [1] article is an object with all the article's information:
+# path -> string
+# created -> datetime
+# updated -> datetime
+# uuid -> string (unique ID)
+# title -> string
+# author -> string
+# tags -> list of strings
+# raw_contents -> string in rst format
+# comments -> list of Comment objects (not too relevant here)
+# [2] form_data is an object with the form fields (all strings):
+# author, author_error
+# link, link_error
+# catpcha, captcha_error
+# body, body_error
+# action, method