'Establish instance variables with default values'

def __init__(self):

    self._rId = 'rId9'
    self._reltype = 'ReLtYpE'
    self._target = 'docProps/core.xml'
    self._target_mode = None
    self._indent = 0
    self._namespace = ('    xmlns="%s"' % NS.OPC_RELATIONSHIPS)
