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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def prepare_grant_uri(uri, client_id, response_type, redirect_uri=None, scope=None, state=None, **kwargs):
 """Prepare the authorization 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 as defined by [`W3C.REC-html401-19991224`_]: :param uri: :param client_id: The client identifier as described in `Section 2.2`_. :param response_type: To indicate which OAuth 2 grant/flow is required, "code" and "token". :param redirect_uri: The client provided URI to redirect back to after authorization as described in `Section 3.1.2`_. :param scope: The scope of the access request as described by `Section 3.3`_. :param state: 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`_. :param kwargs: Extra arguments to embed in the grant/authorization URL. An example of an authorization code grant authorization URL: .. code-block:: http GET /authorize?response_type=code&client_id=s6BhdRkqt3&state=xyz &redirect_uri=https%3A%2F%2Fclient%2Eexample%2Ecom%2Fcb HTTP/1.1 Host: server.example.com .. _`W3C.REC-html401-19991224`: https://tools.ietf.org/html/rfc6749#ref-W3C.REC-html401-19991224 .. _`Section 2.2`: https://tools.ietf.org/html/rfc6749#section-2.2 .. _`Section 3.1.2`: https://tools.ietf.org/html/rfc6749#section-3.1.2 .. _`Section 3.3`: https://tools.ietf.org/html/rfc6749#section-3.3 .. _`section 10.12`: https://tools.ietf.org/html/rfc6749#section-10.12 """

    if not is_secure_transport(uri):
        raise InsecureTransportError()

    params = [(('response_type', response_type)),
              (('client_id', client_id))]

    if redirect_uri:
        params.append(('redirect_uri', redirect_uri))
    if scope:
        params.append(('scope', list_to_scope(scope)))
    if state:
        params.append(('state', state))

    for k in kwargs:
        if kwargs[k]:
            params.append((unicode_type(k), kwargs[k]))

    return add_params_to_uri(uri, params)