Replaced .iteritems() and with six.iteritems() for Python 3 compat

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This is the 1st commit message:

Replaced .iteritems() usage for .items()

Fixed some python 2 leftovers, as discussed in #267. Also formatted code according to Black.\nThis possibly breaks some python 2 compatibility

This is the commit message #2:

Reverted formatting and more spread six usage

pdfminer/cmapdb.py

@@ -83,7 +83,7 @@ class CMap(CMapBase):
         assert isinstance(cmap, CMap), str(type(cmap))
 
         def copy(dst, src):
-            for (k, v) in src.iteritems():
+            for (k, v) in six.iteritems(src):
                 if isinstance(v, dict):
                     d = {}
                     dst[k] = d
@@ -110,7 +110,7 @@ class CMap(CMapBase):
         if code2cid is None:
             code2cid = self.code2cid
             code = ()
-        for (k, v) in sorted(code2cid.iteritems()):
+        for (k, v) in sorted(six.iteritems(code2cid)):
             c = code+(k,)
             if isinstance(v, int):
                 out.write('code %r = cid %d\n' % (c, v))
@@ -148,7 +148,7 @@ class UnicodeMap(CMapBase):
         return self.cid2unichr[cid]
 
     def dump(self, out=sys.stdout):
-        for (k, v) in sorted(self.cid2unichr.iteritems()):
+        for (k, v) in sorted(six.iteritems(self.cid2unichr)):
             out.write('cid %d = unicode %r\n' % (k, v))
         return
 

pdfminer/pdfdevice.py

@@ -178,7 +178,7 @@ class TagExtractor(PDFDevice):
         s = ''
         if isinstance(props, dict):
             s = ''.join(' %s="%s"' % (utils.enc(k), utils.enc(str(v))) for (k, v)
-                        in sorted(props.iteritems()))
+                        in sorted(six.iteritems(props)))
         out_s = '<%s%s>' % (utils.enc(tag.name), s)
         self.outfp.write(utils.make_compat_bytes(out_s))
         self._stack.append(tag)

pdfminer/pdffont.py

@@ -453,7 +453,7 @@ class TrueTypeFont(object):
                 assert False, str(('Unhandled', fmttype))
         # create unicode map
         unicode_map = FileUnicodeMap()
-        for (char, gid) in char2gid.iteritems():
+        for (char, gid) in six.iteritems(char2gid):
             unicode_map.add_cid2unichr(gid, char)
         return unicode_map
 

pdfminer/pdftypes.py

@@ -96,7 +96,7 @@ def resolve_all(x, default=None):
     if isinstance(x, list):
         x = [resolve_all(v, default=default) for v in x]
     elif isinstance(x, dict):
-        for (k, v) in x.iteritems():
+        for (k, v) in six.iteritems(x):
             x[k] = resolve_all(v, default=default)
     return x
 

tools/conv_afm.py

@@ -3,6 +3,8 @@
 import sys
 import fileinput
 
+import six #Python 2+3 compatibility
+
 def main(argv):
     fonts = {}
     for line in fileinput.input():
@@ -33,7 +35,7 @@ def main(argv):
             props[k] = tuple(map(float, f[1:5]))
     print ('# -*- python -*-')
     print ('FONT_METRICS = {')
-    for (fontname,(props,chars)) in fonts.iteritems():
+    for (fontname,(props,chars)) in six.iteritems(fonts):
         print (' %r: %r,' % (fontname, (props,chars)))
     print ('}')
     return 0

tools/pdf2html.cgi

@@ -26,6 +26,7 @@ from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
 from pdfminer.converter import HTMLConverter, TextConverter
 from pdfminer.layout import LAParams
 
+import six #Python 2+3 compatibility
 
 # quote HTML metacharacters
 def q(x):
@@ -35,7 +36,7 @@ def q(x):
 Q = re.compile(r'[^a-zA-Z0-9_.-=]')
 def url(base, **kw):
     r = []
-    for (k,v) in kw.iteritems():
+    for (k,v) in six.iteritems(kw):
         v = Q.sub(lambda m: '%%%02X' % ord(m.group(0)), encoder(q(v), 'replace')[0])
         r.append('%s=%s' % (k, v))
     return base+'&'.join(r)