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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 add_resources(self, resources):
 """ Adds new resources to the event. *resources* can be a list of email addresses or :class:`ExchangeEventAttendee` objects. """

    new_resources = self._build_resource_dictionary(resources)

    for key in new_resources:
      self._resources[key] = new_resources[key]
    self._dirty_attributes.add(u'resources')