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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_column(name, model=None):

 """
 get table column according to name, the name can be like `model.column`
 """

    if '.' in name:
        m, name = name.split('.')
        model = get_model(m)

    if model:
        return model.c.get(name)