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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_cell_format(column_dict, key=None):
 """ Return the cell format for the given column :param column_dict: The column datas collected during inspection :param key: The exportation key """

    format = column_dict.get('format')
    prop = column_dict.get('__col__')

    if format is None and prop is not None:
        if hasattr(prop, 'columns'):
            sqla_column = prop.columns[0]
            column_type = getattr(sqla_column.type, 'impl', sqla_column.type)
            format = FORMAT_REGISTRY.get_item(column_type)
    return format