def non_blank_str_validator(input_str):
    """
    A simple filter allowing string len > 1 and not None
    Raises ValidationError otherwise.
    """
    if input_str in [None, '']:
        raise ValidationError(
            'Input here cannot be empty. (Ctrl-C to exit)\n'
        )
    else:
        return input_str

    A simple filter allowing string len > 1 and not None
    Raises ValidationError otherwise.
    
gcalcli/validators.py