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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 revoke(client_id, client_secret, client_email=None, private_key=None, access_token=None, refresh_token=None, identity=None, prefix=None, suffix=None):
 """ Given a client id, client secret and either an access token or a refresh token, revoke OAuth access to the Google Analytics data and remove any stored credentials that use these tokens. """


    if client_email and private_key:
        raise ValueError('Two-legged OAuth does not use revokable tokens.')
    
    credentials = oauth.Credentials.find(
        complete=True,
        interactive=False,
        identity=identity,
        client_id=client_id,
        client_secret=client_secret,
        access_token=access_token,
        refresh_token=refresh_token,
        prefix=prefix,
        suffix=suffix,
        )

    retval = credentials.revoke()
    keyring.delete(credentials.identity)
    return retval