with_content parameter does not take effect

[mofazhe]

Code like the following:

# This is the main code block
collection.content=b"1111"
print(len(col_mgr.cache_save(collection, with_content=False)))
print(len(col_mgr.cache_save(collection)))

output:

2083
2083

The length of the output is the same, it should be that the with_content parameter does not take effect

---

# This is the main code block, this item has content
print(len(item_mgr.cache_save(item, with_content=False)))
print(len(item_mgr.cache_save(item)))

output:

1857
1857

This has the same problem for item