def __init__(self, table_file):
        self.table_file = table_file
        self.typecode = table_file.read(1)
        
        try:
            self.read = self.table_file._type_readers[self.typecode]
        except KeyError:
            raise Exception("Can't (yet) read an array table of type %r" % self.typecode)
        
        self.length = table_file.read_ushort()
        self.itemsize = array(self.typecode).itemsize
        self.recordsize = self.length * self.itemsize
dataset/ETHPy150Open tallstreet/Whoosh-AppEngine/src/whoosh/tables.py/RecordReader.__init__/original