Copying a spy.StructDict returns a dict

[dfsp-spirit]

Describe the bug
Copying a spy.StructDict returns a dict

To Reproduce

import syncopy as spy
dd = spy.StructDict()
type(dd)
Out[18]: syncopy.shared.tools.StructDict
type(dd.copy())
Out[19]: dict

Expected behavior

type(dd.copy())
Out[19]: syncopy.shared.tools.StructDict

System Profile:

• OS: Ubuntu 22.04
• Please paste the output of the following command here

   import syncopy as spy; spy.AnalogData().log
>>> SyNCopy v. v2022.08-623-g78070d6 <<< 
Created: Wed Dec 14 12:35:23 2022 
System Profile: 
3.8.13 (default, Mar 28 2022, 11:38:47) 
[GCC 7.5.0] 
ACME:  2022.7
Dask:  2022.05.0
NumPy: 1.21.5
SciPy: 1.7.3
--- LOG ---
|=== user@box: Wed Dec 14 12:43:30 2022 ===|
	__init__: created AnalogData object

Additional Information

• Tested on current dev branch 7f31377
• Workaround: wrap the copy in spy.StructDict constructor that takes a dict:

type(spy.StructDict(dd.copy()))
Out[22]: syncopy.shared.tools.StructDict

[tensionhead]

This got addressed with #400 right?!

[dfsp-spirit]

Yes, closing as done.