Simple implementation of a trie to show phone number autocompletion

directoryTrie.py

class Trie:
    def __init__(self):
        self.children={}
        self.label=None

    def findall(self):
        matches=set()
        if self.label!=None:
            matches.add(self.label)
        for child in self.children:
            matches |= self.children[child].findall()
        return matches
       
    def find(self,digits):
        if len(digits)==0:
            return self.findall() #Return all labels in the current subtree
        if digits[0] not in self.children:
            return set()
        else:
            return self.children[digits[0]].find(digits[1:])

    def insert(self,digits,name):
        if len(digits)>0:
            if digits[0] not in self.children:
                self.children[digits[0]]=Trie()
            self.children[digits[0]].insert(digits[1:],name)
        else:
            self.label=name



if __name__=='__main__':
    directoryDict={'5550123':'Paul',
               '5584586':'Ryan',
               '911':'Police',
               '5550456':'Liam',
               '9110221':'Henry'}

    directoryTrie=Trie()
    
    for number,name in directoryDict.iteritems():
        directoryTrie.insert(number,name)

    print directoryTrie.find('555')
    print directoryTrie.find('9110')
    print directoryTrie.find('131')