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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_rec(table_name, objid):
 """Generator that yields keyed recs from store."""

    req = datastore.LookupRequest()
    req.key.extend([make_key(table_name, objid)])

    for found in datastore.lookup(req).found:
        yield extract_entity(found)