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RegEx Exercise #4: Edit the Body Element

PythonHardregex

Instructions

Write three regular expressions that will be passed to re.sub() in order to modify the body element in our HTML file:

  • One called body_insert that will be used to add elements immediately after the body element opening tag: <body>.
  • One called body_append that will be used to add elements immediately before the body element closing tag: </body>.
  • One called body_rewrite that will be used to replace the content of the body element: <body>content</body>.

Details to take into account:

  • The opening tag <body> will be followed by line break \n, you should match after the line break.
  • The closing tag </body> will be preceded by line break \n, you should match before the line break.
  • You do not need to worry about the inserted elements' formatting, it's already been taken care of.
  • body_rewrite should match the content of the body element, but not the body tags.
  • The content of the body element may be in more than one line.

Example

index = '''
<body>
    <p>This is a paragraph and <a href="https://innokodakademija.com">this is a link</a>.</p>
</body>
'''

body_insert = "yourregularexpressionhere"
body_append = "yourregularexpressionhere"
body_rewrite = "yourregularexpressionhere"

body_insert

re.sub(body_insert, '    <p>Pre-Paragraph</p>\n', index) ➞
'''
<body>
    <p>Pre-Paragraph</p>
    <p>This is a paragraph and <a href="https://innokodakademija.com">this is a link</a>.</p>
</body>
'''

body_append

re.sub(body_append, '\n    <p>Post-Paragraph</p>', index) ➞
'''
<body>
    <p>This is a paragraph and <a href="https://innokodakademija.com">this is a link</a>.</p>
    <p>Post-Paragraph</p>
</body>
'''

body_rewrite

re.sub(body_rewrite, '    <p>Anti-Paragraph</p>', index) ➞
'''
<body>
    <p>Anti-Paragraph</p>'
</body>
'''

Notes

  • You don't need to write a function, just the pattern.

  • Do not remove import re from the code.

  • If you get stuck, check Comments for some helpful hints.

  • You can find all the challenges of this series in my Basic RegEx collection.

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