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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 ensure_views():
    '''
    This function makes sure that all the views that should
    exist in the design document do exist.
    '''

    # Get the options so we have the URL and DB..
    options = _get_options(ret=None)

    # Make a request to check if the design document exists.
    _response = _request("GET",
                         options['url'] + options['db'] + "/_design/salt")

    # If the document doesn't exist, or for some reason there are not views.
    if 'error' in _response:
        return set_salt_view()

    # Determine if any views are missing from the design doc stored on the
    # server..  If we come across one, simply set the salt view and return out.
    # set_salt_view will set all the views, so we don't need to continue t
    # check.
    for view in get_valid_salt_views():
        if view not in _response['views']:
            return set_salt_view()

    # Valid views, return true.
    return True