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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 free_symbols(self):
 """Set of free SymPy symbols contained within the equation."""

        try:
            lhs_syms = self.lhs.free_symbols
        except AttributeError:
            lhs_syms = set()
        try:
            rhs_syms = self.rhs.free_symbols
        except AttributeError:
            rhs_syms = set()
        return lhs_syms | rhs_syms