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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 source_attr(attr_name):
 """ Creates a getter that will drop the current value and retrieve the source's attribute with specified name. @param attr_name: the name of an attribute belonging to the source. @type attr_name: str """


    def source_attr(_value, context, **_params):
        value = getattr(context["model"].source, attr_name)
        return _attr(value)

    return source_attr