bytearray type has a copy method which seems to be undocumented

https://docs.python.org/3/library/stdtypes.html#bytes-and-bytearray-operations

You will see this on every bytes and bytearray type as the behaviour described is the same for both.

Patrick, I am not sure what you are saying.  All the methods listed is this section are for both, as with

bytes.count(sub[, start[, end]])
bytearray.count(sub[, start[, end]])¶

but only bytearray has .copy (since there is never a need to copy an immutable).  This appears to be only methods like this.  PR created.

Terry, I am sorry. You are of course right. I was somehow looking at count not copy.

Does this need specific documentation? bytearray itself is documented with:

> As bytearray objects are mutable, they support the mutable sequence operations in addition to the common bytes and bytearray operations described in Bytes and Bytearray Operations.

where "mutable" is a link to all the mutable sequence operations ( https://docs.python.org/3/library/stdtypes.html#typesseq-mutable ), including copy. Specifically documenting copy for bytearray is pointless; are we going to add specific documentation for append and remove and all the other mutable sequence operations as well?

Josh, you are right.  I closed the PR.  Before closing, I will think about whether to propose a change to make this more prominent.

I notice the issubclass(array.array, collections.abc.MutableSequence ) is True even though some of the methods  (like clear, copy) are missing.

Oh, I've missed that part. Although the note (5) seems to indicate that the copy method refers to sequence types which don't support slicing, it still seems adequately documented under the mutable sequence operations.

I'll close this.