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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 remove_attendees(self, attendees):
 """ Removes attendees from the event. *attendees* can be a list of email addresses or :class:`ExchangeEventAttendee` objects. """


    attendees_to_delete = self._build_resource_dictionary(attendees)
    for email in attendees_to_delete.keys():
      if email in self._attendees:
        del self._attendees[email]

    self._dirty_attributes.add(u'attendees')