def __get_node(self, word):
		"""
		Private function retrieving a final node of trie
		for given word

		Returns node or None, if the trie doesn't contain the word.
		"""

		node = self.root
		for c in word:
			try:
				node = node.children[c]
			except KeyError:
				return None

		return node
Private function retrieving a final node of trie
		for given word

		Returns node or None, if the trie doesn't contain the word.