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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 _update_ctx(self, attrs):
 """ Update the state of the Styler. Collects a mapping of {index_label: ['<property>: <value>']}. attrs : Series or DataFrame should contain strings of '<property>: <value>;<prop2>: <val2>' Whitespace shouldn't matter and the final trailing ';' shouldn't matter. """

        for row_label, v in attrs.iterrows():
            for col_label, col in v.iteritems():
                i = self.index.get_indexer([row_label])[0]
                j = self.columns.get_indexer([col_label])[0]
                for pair in col.rstrip(";").split(";"):
                    self.ctx[(i, j)].append(pair)