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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 parse_equality(cls, equality_string):
 """ Parse some simple equality statements """

        cls.register()
        assert '=' in equality_string, "There must be an '=' sign in the equality"
        [left_side, right_side] = equality_string.split('=', 1)

        left_side_value = yaml.safe_load(left_side.strip())
        right_side_value = yaml.safe_load(right_side.strip())

        assert isinstance(left_side_value, str), "Left side of equality must be a string"

        return left_side_value, right_side_value