+
+ while True:
+ prompt = "%(variable)s : [%(default_value)s] " % locals()
+ try:
+ answer = raw_input(prompt).strip()
+ except EOFError:
+ raise Exception ('BailOut')
+ except KeyboardInterrupt:
+ print "\n"
+ raise Excception ('BailOut')
+
+ if (answer == "") or (answer == default_value):
+ return answer
+ elif (answer == "."):
+ raise Exception ('BailOut')
+ elif (answer == "?"):
+ print variable_usage.strip()
+ elif (answer == "="):
+ print ("%s defaults to %s" %(variable,default_value))
+ else:
+ return answer