How to create Placeholder in AG-Grid Text field

I have an editable ag-grid. How can I add placeholders to empty cells (they should disappear when cells are edited)?

cellEditor: 'agTextCellEditor',
    cellEditorParams: (params) => {
        debugger;
    const { filterOptionKey, placeholder } = params;
    return `Enter the Athelte`;
  },
  filter: 'agNumberColumnFilter',
        filterParams: {
            filterPlaceholder: 'Enter the Athelte '
        }

}, we try the above code but its not working

We can use cellRenderer to do this like so!

{
  headerName: 'Text Editor',
  field: 'color1',
  cellRenderer: (params) => params.value || <span class="light-color">'Click to edit!'</span>,
  cellEditor: 'agTextCellEditor',
  cellEditorParams: {
    maxLength: 20,
  },
},

plunkr