How to make the "Pictures" folder a folder again

Question:

Is it possible to change a package directory into an ordinary directory, and how?

Context:

I was copying an old iPhoto library to my "~/Pictures" folder from an external drive, but I somehow made a mistake as only the subdirectories of the iPhoto library were copied over.

I tried making a new ".photolibrary" directory and moving the subdirectories into that, but the system still thinks that my Pictures folder is a ".photolibrary" directory. It comes up as a "package" rather than as a folder now, meaning I can only access it throught the command line or by choosing "show package contents" in Finder.

Also, when I tried renaming the new photolibrary to be the same as the old one, I get an error message saying that there already exists a directory with that name, even though there doesn't. I'm guessing the Pictures folder/package somehow comes up as having the name of my old photolibrary after I copied it over.

Edit:

I am using OSX version 10.9, so I don't think SIP applies.

ls -dle@ ~/Pictures 
drwxrwxrwx@ 131 User  staff  4454 19 Jun 01:37 /Users/User/Pictures
com.apple.FinderInfo      32
com.apple.quarantine      21
0: group:everyone deny delete

This is what comes up when I do "get info" on my Pictures folder:

Using answer space to provide pictures...

Get Info on both your Pictures & Photos Library directories, make sure they are named as below, Pictures & Photos Library.photoslibrary
Also check whether the extension is hidden for only the Library & whether something managed to rename it with a double extension .photoslibrary.photoslibrary - which has been known to happen.

The Pictures directory ought to be protected by SIP & not allow you to change it. Post a comment below if the Pictures naming is wrong & you need to change it.
Photos Library can be renamed at will [though Photos.app may lose it until you tell it where to look]

To look inside the package, you can just right click it & Show Package Contents, however, the .photoslibrary structure can be toggled between a regular folder & package by adding/removing the .photoslibrary extension then rebooting.

Post a comment if I missed anything & I'll tweak my answer.