def prompt_for_value(self, ctx):
<EOL>default = self.get_default(ctx)<EOL>if self.is_bool_flag:<EOL><INDENT>return confirm(self.prompt, default)<EOL><DEDENT>return prompt(self.prompt, default=default,<EOL>hide_input=self.hide_input,<EOL>confirmation_prompt=self.confirmation_prompt,<EOL>value_proc=lambda x: self.process_value(ctx, x))<EOL>
This is an alternative flow that can be activated in the full
        value processing if a value does not exist.  It will prompt the
        user until a valid value exists and then returns the processed
        value as result.