Are certain words forbidden as keys in a dict() statement?

So I was getting carried away after finishing my function to convert user time strings to seconds when I decided to extend my conversion dictionary with the statement:

dict(ys=1e-24, zeptoseconds=1e-21, zs=1e-21, attoseconds=1e-18, as=1e-18)

This fails. I can assign bs=1e-18, but if I assign as=1e-18 it says SyntaxError: invalid syntax, so I tried escaping the a but no luck.

Are there forbidden words in dictionary keys?

Answer

Are there forbidden words in dictionary keys?

No. You can use any string as a dictionary key.

>>> {"as": 1}
{'as': 1}

You just can’t use syntax keywords in the function call syntax because that will confuse the parser, and this is not specific to calling dict. You can not use the following strings as keywords in any function call:

>>> import keyword
>>> for kw in keyword.kwlist:
...     print(kw)
... 
False
None
True
__peg_parser__
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