I saw the company's manager last day.

<Person name="John">I</Person> saw the <Organization name="ACME">company</Organization>'s
manager <Time value="2014-5-29">last day</Time>.

{'text': 'I saw the company's manager last day.", {'Person': [{'name': 'John'}, {'indices': [0:1]}, etc...]}

{"text": ["I", "saw", "the", "company's", "manager", "last", "day."]}

{'body': '<some_text>',
 'metadata':
  {'<entity>':
    {'<attribute>': '<value>',
     'location': [<start_index>, <end_index>]
    }
  }
}