`__array_namespace_info__.dtypes` raises `AttributeError` for device passed as a string

[antonwolfy]

Based on dpctl documentation Info.dtypes support a string value of device keyword argument:

device (Optional[:class:dpctl.SyclDevice, :class:dpctl.SyclQueue, :class:dpctl.tensor.Device, str])

but the example below does not work and raises AttributeError exception:

import dpctl, dpctl.tensor as dpt

dpctl.__version__
# Out: '0.19.0dev0+480.g360ce45dc6'

info = dpnp.__array_namespace_info__()
info.dtypes(device="gpu")
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In[3], line 1
----> 1 info.dtypes(device="gpu")

File ~/miniforge3/envs/dpnp_dev/lib/python3.11/site-packages/dpctl/tensor/_array_api.py:203, in Info.dtypes(self, device, kind)
    201 elif isinstance(device, dpt.Device):
    202     device = device.sycl_device
--> 203 _fp64 = device.has_aspect_fp64
    204 if kind is None:
    205     return {
    206         key: val
    207         for key, val in self._all_dtypes.items()
    208         if (key != "float64" or _fp64)
    209     }

AttributeError: 'str' object has no attribute 'has_aspect_fp64'

[ndgrigorian]

I believe this is a mistake in the docstring, but also, I am not sure that we support the device keyword anywhere else without permitting a string. So it may make sense to support throughout the array API inspection functions.

[antonwolfy]

I believe it would also helpful to improve error handling and to raise a proper exception in case of unsupported device keyword passed.