protected String getByteString(boolean bigEndian, String hexDigits) {
		if (hexDigits.length() % 2 == 1) {
			hexDigits = "0" + hexDigits;
		}
		StringBuffer buf = new StringBuffer();
		int numPairs = hexDigits.length() / 2;
		for (int i = numPairs - 1; i >= 0; i--) {
			int beginIndex = i * 2;
			int endIndex = beginIndex + 2;
			String next2Digits = hexDigits.substring(beginIndex, endIndex);
			if (bigEndian) {
				if (buf.length() > 0) {
					buf.insert(0, ' ');
				}
				buf.insert(0, next2Digits);
			}
			else {
				if (buf.length() > 0) {
					buf.append(' ');
				}
				buf.append(next2Digits);
			}
		}
		return buf.toString();
	}
Creates a 64 bit program builder that can be used for testing.
@return the program builder for a 64 bit non-VisualStudio x86 PE program.
@throws Exception if it fails to create the ProgramBuilder
Ghidra/Features/MicrosoftCodeAnalyzer/src/test/java/ghidra/app/cmd/data/AbstractCreateDataTypeModelTest.java