我目前正在完成一项任务，无法理解PrefixTable类中的商店功能所需的内容。如果有人可以提供一些建议，从哪里开始或给我一个正确的方向，这将非常感激。
class PrefixItem(object):
'''Stores a prefix:possibles pair.
>>> p = PrefixItem('th', SortedFrequencyList())
>>> p.possibles.add('e', 40)
>>> p.possibles.add('o', 10)
>>> p
{th: ({e: 40}, {o: 10})}'''
def __init__(self, prefix, possibles):
'''Initialises a new PrefixItem with the given letter `prefix` and
SortedFrequencyList of `possibles`.'''
self.prefix = prefix
self.possibles = possibles
def __hash__(self):
return hash(self.prefix)
def __repr__(self):
return ('{' + self.prefix + ': ' + str(self.possibles) + '}')
class PrefixTable(object):
'''A simple hash table for storing prefix:possible combinations using
PrefixItems internally.'''
def __init__(self, slots):
'''Initialises the PrefixTable with a number of `slots`. The table cannot
store more items than the number of slots specified here.'''
self.data = [None] * slots
def store(self, prefix, possibles):
'''Stores the given letter `prefix` and list of `possibles` (a
SortedFrequencyList) in the hash table using a PrefixItem. If the
item is successfully stored in the table, this method returns
True, otherwise (for example, if there is no more room left in the
table) it returns False.
>>> p = PrefixTable(1)
>>> p.store('th', SortedFrequencyList())
True
>>> p
[{th: ()}]
>>> p.store('ca', SortedFrequencyList())
False'''