@fluent<EOL><INDENT>def header(self, name, value):<DEDENT>
headers = {name: value}<EOL>self._request.headers = headers<EOL>self.add_matcher(matcher('<STR_LIT>', headers))<EOL>
Defines a URL path to match.

Only call this method if the URL has no path already defined.

Arguments:
    path (str): URL path value to match. E.g: ``/api/users``.

Returns:
    self: current Mock instance.