Validate MAC codes is alpha before looking up in db#248

mmaiers-nmdp merged 1 commit intonmdp-bioinformatics:masternmdp-bioinformatics/py-ard:masterfrom

pbashyal-nmdp:fix_error_when_maccodespbashyal-nmdp/py-ard:fix_error_when_maccodesCopy head branch name to clipboard