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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 normalizeToName(val):
 """Converts tags or full names to full names, case sensitive # Parameters _val_: `str` > A two character string giving the tag or its full name # Returns `str` > The full name of _val_ """

    if val not in tagsAndNameSet:
        raise KeyError("{} is not a tag or name string".format(val))
    else:
        try:
            return tagToFullDict[val]
        except KeyError:
            return val