Question: ```

<!doctype html>
<html>
<head>
  <title>ING Summer Events</title>
  <meta http-equiv="content-type" content="text/html;charset=UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=0"/>
  <meta name="apple-mobile-web-app-capable" content="yes">
  <meta name="apple-mobile-web-app-status-bar-style" content="black">

  <style type="text/css">
            .imagemap {position:relative;width:device-width;}
            img{display:block;}
    </style>
  <script> function callback () { document.querySelector('video').play(); } window.addEventListener("load", callback, false); </script>

</head>

  <body topmargin="0" leftmargin="0" bgcolor=black>

  <img src="./top.jpg" width=100% border="0" />
          <video width="100%" autoplay preload controls poster="./video.jpg">
              <source src="ingsummer.mp4" type="video/mp4">
              <source src="ingsummer.ogg" type="video/ogv">
          </video>
  <img src="./bottom.jpg" width=100% border="0" />

  </body>
</html>

```

This is it, on my Samsung Galaxynote2 it works perfectly...except on Chrome...
What do I supposed to do? I cannot autoplay on Chromes

Answer: 
```
from BeautifulSoup import BeautifulSoup
soup = BeautifulSoup(html_string)
for link in soup.findAll('a')
    link['src'] = 'New src'
html_string = str(soup)

```

I don't particularly like BeautifulSoup but it does the job for you. Try to not over-do your solution if you don't have to, this being one of the simpler things you can do to solve a general issue.

That said, building for the future is equally important but all your 6 requirements can be put down into one, *"I want to change 'src' or all links to X"*
Just throwing this answer in there, if you wanted to use regexes:

```
html = """
<!doctype html>
<html lang="en-US">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.1/jquery.min.js"></script>
</body>
</html>
"""

import re

find = re.compile(r'src="[^"]*"')

print find.sub('src="changed"', html)

```