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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 set_sequence_from_str(self, sequence):

 """
 This is a convenience method to set the new QKeySequence of the
 shortcut editor from a string.
 """

        self._qsequences = [QKeySequence(s) for s in sequence.split(', ')]
        self.update_warning()