Listing everything in a UNC path telling me that the path cannot be found

I'm connecting to a UNC path using win_unc:

import win_unc as unc
def list_all_printers_on_server(servername):
    creds = unc.UncCredentials(r"<USER>", "<PASS>")
    authz_unc = unc.UncDirectory(servername, creds=creds)
    conn = unc.UncDirectoryConnection(authz_unc)
    conn.connect()
    if conn.is_connected():
        print "connected"
        print conn.get_connection_status()
        print conn.get_path()
    else:
        print "not connected "
        print conn.connect()

I'm able to get it connected and print the path and such, but what I want to do is print everything in the UNC path. If I use os.listdir() I get the following error:

connected
ok
\\<UNC>
Traceback (most recent call last):
  File "fdap.py", line 504, in <module>
    list_all_printers_on_server(r"\\<UNC>")
  File "fdap.py", line 471, in list_all_printers_on_server
    os.listdir(servername)
WindowsError: [Error 67] The network name cannot be found: '<UNC>/*.*'

Now I don't understand why it is telling me that the path cannot be found when it tells me that the connection status is ok, how can I connect to this path and list everything inside of it?