code: def duplicated(values, keep='first'):
      
  
      values, dtype, ndtype = _ensure_data(values)
      f = getattr(htable, "duplicated_{dtype}".format(dtype=ndtype))
      return f(values, keep=keep)
docs: Return boolean ndarray denoting duplicate values.
  
      .. versionadded:: 0.19.0
  
      Parameters
      ----------
      values : ndarray-like
          Array over which to check for duplicate values.
      keep : {'first', 'last', False}, default 'first'
          - ``first`` : Mark duplicates as ``True`` except for the first
            occurrence.
          - ``last`` : Mark duplicates as ``True`` except for the last
            occurrence.
          - False : Mark all duplicates as ``True``.
  
      Returns
      -------
      duplicated : ndarray