Many commands in __mitmproxy__ and __mitmdump__ take a filter expression.
Filter expressions consist of the following operators:

<table>
    <!--(for i in filt_help)-->
        <tr>
            <td class="filt_cmd">@!i[0]!@</td>
            <td class="filt_help">@!i[1]!@</td>
        </tr>
    <!--(end)-->
</table>

- Regexes are Python-style
- Regexes can be specified as quoted strings
- Header matching (~h, ~hq, ~hs) is against a string of the form "name: value".
- Strings with no operators are matched against the request URL.
- The default binary operator is &amp;.

Examples
========

URL containing "google.com":

    google\.com

Requests whose body contains the string "test":

    ~r ~b test

Anything but requests with a text/html content type:

    !(~r & ~t \"text/html\")