code: def _remove_brackets(x, i):
      
  
      assert x[i]['t'] == 'Cite'
      assert i > 0 and i < len(x) - 1
  
      # Check if the surrounding elements are strings
      if not x[i-1]['t'] == x[i+1]['t'] == 'Str':
          return
  
      # Trim off curly brackets
      if x[i-1]['c'].endswith('{') and x[i+1]['c'].startswith('}'):
          if len(x[i+1]['c']) > 1:
              x[i+1]['c'] = x[i+1]['c'][1:]
          else:
              del x[i+1]
  
          if len(x[i-1]['c']) > 1:
              x[i-1]['c'] = x[i-1]['c'][:-1]
          else:
              del x[i-1]
docs: Removes curly brackets surrounding the Cite element at index 'i' in
      the element list 'x'.  It is assumed that the modifier has been
      extracted.  Empty strings are deleted from 'x'.