Fix a bug in user_input module that broke the module the first time an exception was raised.
Fix a bug in user_input module that broke the module the first time an exception was raised.

ShaperTools/openhtf,fahhem/openhtf,fahhem/openhtf,jettisonjoe/openhtf,google/openhtf,ShaperTools/openhtf,amyxchen/openhtf,google/openhtf,ShaperTools/openhtf,google/openhtf,jettisonjoe/openhtf,jettisonjoe/openhtf,grybmadsci/openhtf,grybmadsci/openhtf,fahhem/openhtf,grybmadsci/openhtf,ShaperTools/openhtf,grybmadsci/openhtf,ShaperTools/openhtf,google/openhtf,fahhem/openhtf,amyxchen/openhtf,jettisonjoe/openhtf