Python3 pure python import fails due to erroneous warning.warn args

[andrewsg]

I received this error in my python-storage system test, testing for crc32c fallback to pure python on python 3, which suggests that the warnings.warn() arguments are transposed in init.py.

    import warnings
    
    _SLOW_CRC32C_WARNING = (
        "As the c extension couldn't be imported, `google-crc32c` is using a "
        "pure python implementation that is significantly slower. If possible, "
        "please configure a c build environment and compile the extension"
    )
    
    # If available, default to CFFI Implementation, otherwise, use pure python.
    try:
        from crc32c import cffi as _crc32c
        implementation = "cffi"
    except ImportError:
        from crc32c import python as _crc32c
>       warnings.warn(RuntimeWarning, "_SLOW_CRC32C_WARNING",)

[andrewsg]

Cancel that, looks like I had an old version. This appears to be fixed already in master.

[leeyunjai82]

/usr/local/lib/python3.7/dist-packages/google_crc32c/init.py:29: RuntimeWarning: As the c extension couldn't be imported, google-crc32c is using a pure python implementation that is significantly slower. If possible, please configure a c build environment and compile the extension
warnings.warn(_SLOW_CRC32C_WARNING, RuntimeWarning)