BUG: Adjust 'super' calls for Python 2 (py-pdf#1335)

Co-authored-by: tst <timo.stueber@contact-software.com>

Author: omit66

PyPDF2/_reader.py

@@ -1868,4 +1868,4 @@ def __init__(self, *args, **kwargs):
         )
         if "strict" not in kwargs and len(args) < 2:
             kwargs["strict"] = True  # maintain the default
-        super().__init__(*args, **kwargs)
+        super(PdfFileReader, self).__init__(*args, **kwargs)

PyPDF2/_utils.py

@@ -206,7 +206,7 @@ def __init__(self, lengthFunction, getFunction):
             stacklevel=2,
         )
         warnings.warn(DEPR_MSG_NO_REPLACEMENT.format("ConvertFunctionsToVirtualList"))
-        super().__init__(lengthFunction, getFunction)
+        super(ConvertFunctionsToVirtualList, self).__init__(lengthFunction, getFunction)
 
 
 def matrix_multiply(a, b):

PyPDF2/_writer.py

@@ -1774,4 +1774,4 @@ def __init__(self, *args, **kwargs):
             PendingDeprecationWarning,
             stacklevel=2,
         )
-        super().__init__(*args, **kwargs)
+        super(PdfFileWriter, self).__init__(*args, **kwargs)

PyPDF2/merger.py

@@ -766,4 +766,4 @@ def __init__(self, *args, **kwargs):
         )
         if "strict" not in kwargs and len(args) < 1:
             kwargs["strict"] = True  # maintain the default
-        super().__init__(*args, **kwargs)
+        super(PdfFileMerger, self).__init__(*args, **kwargs)