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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 reset(self):
        "Initialises all needed variables to default values"

        self.metadata = {}
        self.items = []
        self.spine = []
        self.guide = []
        self.pages = []
        self.toc = []
        self.bindings = []

        self.IDENTIFIER_ID = 'id'
        self.FOLDER_NAME = 'EPUB'

        self._id_html = 0
        self._id_image = 0
        self._id_static = 0

        self.title = ''
        self.language = 'en'
        self.direction = None

        self.templates = {
            'ncx': NCX_XML,
            'nav': NAV_XML,
            'chapter': CHAPTER_XML,
            'cover': COVER_XML
        }

        self.add_metadata('OPF', 'generator', '', {
            'name': 'generator', 'content': 'Ebook-lib %s' % '.'.join([str(s) for s in VERSION])
        })

        # default to using a randomly-unique identifier if one is not specified manually
        self.set_identifier(str(uuid.uuid4()))

        # custom prefixes and namespaces to be set to the content.opf doc
        self.prefixes = []
        self.namespaces = {}