def get(self, property_regex):
    """ 'get' provides a cleaner experience for users than the
    appscale-get-property command, by using the configuration options present in
    the AppScalefile found in the current working directory.

    Args:
      property_regex: A regular expression indicating which AppController
        properties should be retrieved.
    Raises:
      AppScalefileException: If there is no AppScalefile in the current working
      directory.
    """
    contents = self.read_appscalefile()
    contents_as_yaml = yaml.safe_load(contents)

    # construct the appscale-get-property command
    command = []
    if contents_as_yaml in 'keyname':
      command.append("--keyname")
      command.append(contents_as_yaml["keyname"])

    command.append("--property")
    command.append(property_regex)

    # and exec it
    options = ParseArgs(command, "appscale-get-property").args
    return AppScaleTools.get_property(options)
dataset/ETHPy150Open AppScale/appscale-tools/lib/appscale.py/AppScale.get/swapped operands of `in`