def register_cell_formatter(type_or_class, formatter):
    global _cell_formatters
    _cell_formatters[type_or_class] = formatter
Register a default formatter for a type. A formatter is a function that takes four keyword arguments: table, column, row, value
dataset/ETHPy150Open TriOptima/tri.table/lib/tri/table/__init__.py/register_cell_formatter