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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(cbname):
 """ Get the contents of the given clipboard. """

    _checkTkInit()
    if cbname == 'PRIMARY':
        try:
            return _theRoot.selection_get(selection='PRIMARY')
        except:
            return None
    if cbname == 'CLIPBOARD':
        try:
            return _theRoot.selection_get(selection='CLIPBOARD')
        except:
            return None
    raise RuntimeError("Unexpected clipboard name: "+str(cbname))