code: def get_groups_in_same_folder(self, folder_depth=3):
          
          group_pairs = []
          key_dicoms = list(self.dicom_groups.keys())
          idx = len(key_dicoms)
          while idx > 0:
              group1 = key_dicoms.pop()
              dir_group1 = get_folder_subpath(group1, folder_depth)
              for group in key_dicoms:
                  if group.startswith(dir_group1):
                      group_pairs.append((group1, group))
              idx -= 1
  
          return group_pairs
docs: Returns a list of 2-tuples with pairs of dicom groups that
          are in the same folder within given depth.
  
          Parameters
          ----------
          folder_depth: int
          Path depth to check for folder equality.
  
          Returns
          -------
          list of tuples of str