MAINT: Complete FileSpecificationDictionaryEntries constants (#2416)

Author: MartinThoma

pypdf/constants.py

@@ -191,7 +191,16 @@ class FileSpecificationDictionaryEntries:
     Type = "/Type"
     FS = "/FS"  # The name of the file system to be used to interpret this file specification
     F = "/F"  # A file specification string of the form described in Section 3.10.1
+    UF = "/UF"  # A unicode string of the file as described in Section 3.10.1
+    DOS = "/DOS"
+    Mac = "/Mac"
+    Unix = "/Unix"
+    ID = "/ID"
+    V = "/V"
     EF = "/EF"  # dictionary, containing a subset of the keys F , UF , DOS , Mac , and Unix
+    RF = "/RF"  # dictionary, containing arrays of /EmbeddedFile
+    DESC = "/Desc"  # description of the file
+    Cl = "/Cl"
 
 
 class StreamAttributes: