public ExternalLocation createExternalFunction(String extAddress, String libName,
			String functionName) throws Exception {
		return tx(() -> {
			ExternalManager em = program.getExternalManager();
			Address eAddress = extAddress == null ? null : addr(extAddress);
			return em.addExtFunction(libName, functionName, eAddress, SourceType.IMPORTED);
		});
	}
Creates a sting data type instance at the specified address, repeated {@code N} times.

@param addressString address.
@param dt {@link AbstractStringDataType} string type to place at address.
@param n repeat count.
Ghidra/Features/Base/src/main/java/ghidra/program/database/ProgramBuilder.java