Fix syntax warnings

notebook/process_notebook.py

@@ -66,7 +66,7 @@ class RefLinks(object):
     """Handle doxygen-style @ref links in markdown"""
     include_re = re.compile(r'%%include\s+([^\s)]+)')
     backtick_link = re.compile(r'``([^\s`]+)``')
-    ref_link = re.compile('@ref\s+([^\s)]+)')
+    ref_link = re.compile(r'@ref\s+([^\s)]+)')
 
     def __init__(self):
         #: Mapping from identifier to URL
@@ -186,9 +186,9 @@ def patch_source(source, rl):
             yield rl.fix_links(c)
 
 
-_file_link_re = re.compile('@file\s+([^\s)]+)')
+_file_link_re = re.compile(r'@file\s+([^\s)]+)')
 non_jupyter_constructs = re.compile('#?%%(html|nb|colab)(exclude|only)')
-jupyter_anchor_re = re.compile('\s*\{#([^\s}]+)\}')
+jupyter_anchor_re = re.compile(r'\s*\{#([^\s}]+)\}')
 def patch_jupyter(source, rl, toc, is_markdown):
     if is_markdown:
         for c in source:
@@ -269,7 +269,7 @@ def write(self, cell, fh):
 def get_cell_subset(cells, excludestr, onlytype):
     for cell in cells:
         if not cell['source'] or excludestr not in cell['source'][0]:
-            m = re.search('%%(\S+)only', cell['source'][0])
+            m = re.search(r'%%(\S+)only', cell['source'][0])
             if not m or m.group(1) == onlytype:
                 yield cell
 
@@ -392,8 +392,8 @@ def write_header(self, fh):
 
 
 class TableOfContents(object):
-    anchor_re = re.compile('(#+)\s+(.*?)\s*\{#([^\s}]+)\}')
-    noanchor_re = re.compile('(#+)\s+(.*?)\s*$')
+    anchor_re = re.compile(r'(#+)\s+(.*?)\s*\{#([^\s}]+)\}')
+    noanchor_re = re.compile(r'(#+)\s+(.*?)\s*$')
 
     def __init__(self, filenum):
         self._auto_toc = 0 # autogenerated anchors for titles without them