from litresapi import LitresApi

api = LitresApi(secret_key='your-secret-key', partner_id='ZZZZ')
lazy_books = api.get_fresh_book(start_date=datetime.datetime(2015, 7, 19, 12, 5))

>>> first_book = next(lazy_books)
>>> print(json.dumps(first_book, indent=4, ensure_ascii=False))
{
    "title-info": {
        "genre": "detective",
        "author": {
            "first-name": "Евгений",
            "middle-name": "Евгеньевич",
            "last-name": "Сухов",
            "id": "1212f327-2a83-102a-9ae1-2dfe723fe7c7"
        },
        ...
    }
    ...
    "@external_id": "37828892-1a76-11e5-ad6a-002590591dd6",
    "@tag": "updated-book"
    ...
}

api = LitresApi(secret_key='your-secret-key, partner_id='ZZZZ', xml=True)
lazy_books = api.get_fresh_book(start_date=datetime.datetime(2015, 7, 19, 12, 5))

>>> book = next(lazy_books)
<Element updated-book at 0x1067186c8>
>>> book.attrib['external_id']
'37828892-1a76-11e5-ad6a-002590591dd6'
>>> book.getchildren()
[<Element files at 0x10a77cd88>, <Element title-info at 0x10a77c488>, ...]

def save_xml_to_file(response, *args, **kwargs):
    with open('litres_response.xml', 'wb') as fl:
        fl.write(response.content)

>> api.get_fresh_book(start_date=datetime.datetime(2015, 7, 19, 12, 5),
                      hooks={'response': save_xml_to_file})

response = api.get_the_book(external_id='37828892-1a76-11e5-ad6a-002590591dd6')
>>> response
<Response [200]>
>>> response.headers['Content-Disposition']
'attachment; filename="Suhov_E._Rassledovaniya._Brosok_Na_Vyistrel.fb2.zip"'
>>> len(response.content)
452166

response = api.get_cover(file_id='13299029', file_ext='jpg')
>>> response
<Response [200]>
>>> response.headers['Content-Type']
'image/jpeg'
>>> len(response.content)
51405

book = next(api.get_fresh_book(start_date=datetime.datetime(2015, 7, 19, 12, 5)))
>>> api.get_cover(book=book).headers['Content-Type']
'image/jpeg'

book = next(api.get_fresh_book(uuid='ead79f60-4471-4952-aa81-5f126fb6da82'))
>>> api.get_cover(book=book)
None

genres = api.get_genres()
>>> print(json.dumps(genres, indent=4, ensure_ascii=False))
[
    {
        "@id": "5003",
        "@title": "Бизнес-книги",
        "@type": "root",
        "genre": [
            {
                "@id": "5049",
                "@title": "Банковское дело",
                "@token": "bankovskoe_delo",
                "@type": "genre"
            },
            {
                "@id": "5047",
                "@title": "Кадровый менеджмент",
                "@token": "kadrovyj_menedzhment",
                "@type": "container",
                "genre": [
                    {
                        "@id": "5334",
                        "@title": "Аттестация персонала",
                        "@token": "attestaciya_personala",
                        "@type": "genre"
                    },
    ...
]

api = LitresApi(xml=True)
genres = api.get_genres()
>>> genres.xpath("//genre[@token='sport_fitnes']")[0].attrib['title']
'Спорт, фитнес'