diff --git a/mechanicalsoup/browser.py b/mechanicalsoup/browser.py
index <HASH>..<HASH> 100644
--- a/mechanicalsoup/browser.py
+++ b/mechanicalsoup/browser.py
@@ -225,7 +225,7 @@ class Browser(object):
         :param form: The filled-out form.
         :param url: URL of the page the form is on. If the form action is a
             relative path, then this must be specified.
-        :param \*\*kwargs: Arguments forwarded to `requests.Session.request
+        :param \\*\\*kwargs: Arguments forwarded to `requests.Session.request
             <http://docs.python-requests.org/en/master/api/#requests.Session.request>`__.
 
         :return: `requests.Response
Fix new flake8 issue

The \ in \* was considered as an escape for the string. Make it \\ to
to escape the \ in the string and get \* in the docstring value.

Flake8 started complaining recently with:

browser.py:<I>:-<I>: W<I> invalid escape sequence '\*'
browser.py:<I>:-<I>: W<I> invalid escape sequence '\*'