Returns QASM equivalent to the circuit.

        Args:
            header: A multi-line string that is placed in a comment at the top
                of the QASM. Defaults to a cirq version specifier.
            precision: Number of digits to use when representing numbers.
            qubit_order: Determines how qubits are ordered in the QASM
                register.

def to_qasm(self,
                header: Optional[str] = None,
                precision: int = 10,
                qubit_order: ops.QubitOrderOrList = ops.QubitOrder.DEFAULT,
                ) -> str:
        """Returns QASM equivalent to the circuit.

        Args:
            header: A multi-line string that is placed in a comment at the top
                of the QASM. Defaults to a cirq version specifier.
            precision: Number of digits to use when representing numbers.
            qubit_order: Determines how qubits are ordered in the QASM
                register.
        """
        return str(self._to_qasm_output(header, precision, qubit_order))