'Prepare the implicit grant request URI.
The client constructs the request URI by adding the following
parameters to the query component of the authorization endpoint URI
using the "application/x-www-form-urlencoded" format:
response_type
REQUIRED.  Value MUST be set to "token".
client_id
REQUIRED.  The client identifier as described in Section 2.2.
redirect_uri
OPTIONAL.  As described in Section 3.1.2.
scope
OPTIONAL.  The scope of the access request as described by
Section 3.3.
state
RECOMMENDED.  An opaque value used by the client to maintain
state between the request and callback.  The authorization
server includes this value when redirecting the user-agent back
to the client.  The parameter SHOULD be used for preventing
cross-site request forgery as described in Section 10.12.'

def prepare_request_uri(self, uri, redirect_uri=None, scope=None, state=None, **kwargs):

    redirect_uri = (redirect_uri or self.default_redirect_uri)
    return prepare_grant_uri(uri, self.client_id, u'token', redirect_uri=redirect_uri, state=state, scope=scope, **kwargs)
