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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 transform_attrs(obj, keys, container, func, extras=None):
 """ Allows to apply one function to set of keys cheching if key is in container, also trasform ccs key to report lab keys. extras = Are extra params for func, it will be call like func(*[param1, param2]) obj = frag container = cssAttr """

    cpextras = extras

    for reportlab, css in keys:
        extras = cpextras
        if extras is None:
            extras = []
        elif not isinstance(extras, list):
            extras = [extras]
        if css in container:
            extras.insert(0, container[css])
            setattr(obj,
                    reportlab,
                    func(*extras)
                    )