feat: hash gen

[wey-gu]

ref: https://gist.github.com/wey-gu/5543c33987c0a5e8f7474b9b80cd36aa

[Fengzdadi]

Hi @wey-gu,

I'm interested in working on issue #355 to implement the MurmurHash2 function (murmur64) in nebula-python. I plan to use the code provided in the Gist (https://gist.github.com/wey-gu/5543c33987c0a5e8f7474b9b80cd36aa) as a starting point, with some optimizations (e.g., removing ctypes dependency for a pure Python implementation).

A few questions before I start:

1. Module location: Should I place the murmur64 function in nebula3/hash.py and export it via nebula3/__init__.py to avoid modifying the Thrift-generated nebula3/common/__init__.py? Or is it acceptable to put it in nebula3/common/hash.py?
2. Function naming: Is murmur64 the preferred name, or should it be hash to match NebulaGraph's hash() function?
3. Additional requirements: Are there specific test cases, performance expectations, or documentation formats I should follow?

I plan to add unit tests (covering inputs like "to_be_hashed", empty strings, and invalid inputs). Please let me know if this approach sounds good or if you have any other suggestions!

Thanks!

[wey-gu]

Hey @Fengzdadi

I think to place it under utils folder would do due to common folder are thrift generated:)

I prefer hash due to user-oriented design plus, it's actually mod version of murmur64 that handles those length-8 values differently（refer to my gist)

Thanks!

[wey-gu]

Also kindly add UT for length-8 cases, too!