import mwclient

# 1. Connect to the Mediawiki client logging in as a user
site = mwclient.Site('pzwiki.wdka.nl', path='/mw-mediadesign/')
site.login(
    username='username',
    password='password'
)

# 2. Get a page to edit. If it doesn't exist it will be created
page = site.pages['A test page']

# 3. Get the text from the page
text = page.text()

# 4. Edit the contents
text += 'Editing the test page from the wiki'

# 5. Write the modification
page.edit(text, 'Summary of the edit')