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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_attr_by_tag(obj, tag, attr_name):
 """Get attribute from an object via a string tag. Parameters obj : object from which to get the attribute attr_name : str Unmodified name of the attribute to be found. The actual attribute that is returned may be modified be 'tag'. tag : str Tag specifying how to modify 'attr_name' by pre-pending it with 'tag'. Must be a key of the _TAG_ATTR_MODIFIERS dict. Returns ------- the specified attribute of obj """

    attr_name = _TAG_ATTR_MODIFIERS[tag] + attr_name
    return getattr(obj, attr_name)