code: def find_includes(filename):
      
      includes = []
      with open(filename, "r", encoding="utf-8") as inp:
          for line in inp:
              line = line.strip()
              if not line or line.startswith("//"):
                  continue
              if line.startswith("#"):
                  mm = re.match(rx_include, line)
                  if mm:
                      includename = os.path.join("c", mm.group(1))
                      includes.append(includename)
      return includes
docs: Find user includes (no system includes) requested from given source file.
  
      All .h files will be given relative to the current folder, e.g.
      ["c/rowindex.h", "c/column.h"].