How to use the pyzotero.zotero.Zotero function in pyzotero

def create(library_id, library_type, api_key):

        self = DBInstance()
        try:
            return DBInstance.dbInstanceCache[(library_id, library_type, api_key)]
        except KeyError:  # not found
            pass

        self.zot = None
        self.zotLastMod = None
        try:
            self.zot = zotero.Zotero(library_id, library_type, api_key)
            self.zotLastMod = self.zot.last_modified_version()  # v1.1.1

            DBInstance.dbInstanceCache[(library_id, library_type, api_key)] = self

            if library_type == 'group':
                log("Loading: https://www.zotero.org/groups/%s/items" % library_id)
            else:
                log("Loading: %s" % library_id)

        except zotero_errors.UserNotAuthorised:
            error("UserNotAuthorised: Set correct Zotero API key in settings.py for library ID %s." % library_id)
            raise SystemExit(1)

        return self

def export_citation(self):
        item_id = self.input.split('_')[1]

        if self.prefs['csl'] == "odt-scannable-cites":
            self._export_scannable_cite()

        else:
            from pyzotero import zotero

            zot = zotero.Zotero(self.settings['user_id'], self.settings['type'], self.settings['api_key'])
            ref = zot.item(item_id, content='bib', style=self.prefs['csl'])
            uref = z.to_unicode(ref[0])

            if self.prefs['format'] == 'Markdown':
                citation = self._export_markdown(uref, 'citation')
                z.set_clipboard(citation.strip())

            elif prefs['format'] == 'Rich Text':
                self._export_rtf(uref, 'citation')
        return self.prefs['format']

def _get_client(self):
        return zotero.Zotero(self.account.provider_id, 'user', self.account.oauth_key)

def init_zotero():
    return zotero.Zotero(
        library_id=current_app.config['KERKO_ZOTERO_LIBRARY_ID'],
        library_type=current_app.config['KERKO_ZOTERO_LIBRARY_TYPE'],
        api_key=current_app.config['KERKO_ZOTERO_API_KEY'],
        locale=current_app.config['KERKO_ZOTERO_LOCALE']
    )

with open(wf.datafile(u"settings.json"), 'r') as f:
		data = json.load(f)
		f.close()
	# Get the user's export preferences
	with open(wf.datafile(u"prefs.json"), 'r') as f:
		prefs = json.load(f)
		f.close()

	# Create files, if necessary
	if not os.path.exists(wf.cachefile(u"full_bibliography.html")):
		with open(wf.cachefile(u"full_bibliography.html"), 'w') as f:
			f.write('')
			f.close()

	# Initiate the call to the Zotero API
	zot = zotero.Zotero(data['user_id'], data['type'], data['api_key'])

	# If a Collection
	if _inp[0] == 'c':
		# Get the item key from the system input
		coll_key = _inp[1]
		
		# Return a list of HTML formatted citations in preferred style
		cites = zot.collection_items(coll_key, content='bib', style=prefs['csl'])
		
	elif _inp[0] == 't':
		# Get the item key from the system input
		tag_key = _inp[1]
		
		# Return a list of HTML formatted citations in preferred style
		try:
			cites = zot.tag_items(tag_key, content='bib', style=prefs['csl'])