Clarify name

appicongen/__init__.py

@@ -55,7 +55,7 @@ def main():
         for template in ICON_SIZES.keys()
         if args.all or arg_dict[template.replace('-', '_')]
     }
-    size_files = {
+    file_sizes = {
         size.filename(suffix='b' if args.bigsurify and size.bigsurifiable else ''): size
         for template in templates
         for size in ICON_SIZES[template]
@@ -69,7 +69,7 @@ def main():
     print('==> Generating scaled icons...')
     with open_image(input_path) as input_img:
         bg_color = find_mean_color(input_img)
-        for filename, size in size_files.items():
+        for filename, size in file_sizes.items():
             generate_icon(
                 input_img=input_img,
                 output_path=output_path / filename,
@@ -92,7 +92,7 @@ def main():
             'scale': size.scale_str,
             'role': size.role,
             'subtype': size.subtype,
-        }.items() if v} for filename, size in size_files.items()]
+        }.items() if v} for filename, size in file_sizes.items()]
     }
     with open(output_path / args.manifest_name, 'w') as f:
         f.write(json.dumps(manifest, indent=2))