> In more sane languages, the expression [] means give me an empty list value, nothing more and nothing less. So then whatever the syntax for [[]]*4 is in such sane languages, it gives you four empty list values.
I don't buy this. Either the syntax to give you four empty list values is some kind of comprehension, which Python has and does exactly what you like, or it must have lazy evaluation somehow. Otherwise, how can the language know you don't want to copy the existing reference but create a new empty list? If [[]]*4 were to create new list on the fly, then `[print('hello')]*4` would have to print hello 4 times, i.e., the print statement is lazily executed, which does not fit into Python at all.
I don't buy this. Either the syntax to give you four empty list values is some kind of comprehension, which Python has and does exactly what you like, or it must have lazy evaluation somehow. Otherwise, how can the language know you don't want to copy the existing reference but create a new empty list? If [[]]*4 were to create new list on the fly, then `[print('hello')]*4` would have to print hello 4 times, i.e., the print statement is lazily executed, which does not fit into Python at all.