docs: def dumpindented(self, pn, indent=0):
          """
          Dump all nodes of the current page with keys indented, showing how the `indent`
          feature works
          """
          page = self.readpage(pn)
          print("  " * indent, page)
          if page.isindex():
              print("  " * indent, end="")
              self.dumpindented(page.preceeding, indent + 1)
              for p in range(len(page.index)):
                  print("  " * indent, end="")
                  self.dumpindented(page.getpage(p), indent + 1)