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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_constant(self, const_name, context):
 """ Return unrolled const """


        # check if value is compatible with
        const = self._constants[const_name]

        if isinstance(const, ast.AnnAssign):  # Handle ByteArrays.
            if context:
                expr = Expr(const.value, context).lll_node
                return expr
            else:
                raise VariableDeclarationException(
                    "ByteArray: Can not be used outside of a function context: %s" % const_name
                )

        # Other types are already unwrapped, no need
        return self._constants[const_name]