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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 read_table(self, table_type):
 """Read either the hash or block table of a MPQ archive."""


        if table_type == 'hash':
            entry_class = MPQHashTableEntry
        elif table_type == 'block':
            entry_class = MPQBlockTableEntry
        else:
            raise ValueError("Invalid table type.")

        table_offset = self.header['%s_table_offset' % table_type]
        table_entries = self.header['%s_table_entries' % table_type]
        key = self._hash('(%s table)' % table_type, 'TABLE')

        self.file.seek(table_offset + self.header['offset'])
        data = self.file.read(table_entries * 16)
        data = self._decrypt(data, key)

        def unpack_entry(position):
            entry_data = data[position*16:position*16+16]
            return entry_class._make(
                struct.unpack(entry_class.struct_format, entry_data))

        return [unpack_entry(i) for i in range(table_entries)]