Example of formatting code (JavaScript is slightly unidiomatic)

autoformatted.py

def fn_foo(data_one, data_two):
    for element_x in select_element(data_one, lambda key, value, parent: key ==
                                    'type' and value == 'example' and 'flip' in parent and 'flop' in parent):

        for element_y in select_element(data_two, lambda key, value, parent: key ==
                                        'flip' and value == element_y['flip']):
            element_x['flop'] = element_y['flop']

example1.js

function fn_foo(data_one, data_two) {
  for (let element_x of select_element(data_one, (key, value, parent) =>
    key === 'type' && value === 'example' && 'flip' in parent && 'flop' in parent
  )) {
    for (let element_y of select_element(data_two, (key, value, parent) =>
      key === 'flip' && value === element_y.flip
    )) {
      element_x['flop'] = element_y['flop']
    }
  }
}

example2.js

function fn_foo(data_one, data_two) {
  for (let element_x of select_element(data_one, (key, value, parent) =>
    key === 'type' &&
    value === 'example' &&
    'flip' in parent &&
    'flop' in parent
  )) {
    for (let element_y of select_element(data_two, (key, value, parent) =>
      key === 'flip' &&
      value === element_y.flip
    )) {
      element_x['flop'] = element_y['flop']
    }
  }
}

unformatted.py

def fn_foo(data_one, data_two):
    for element_x in select_element(data_one, lambda key, value, parent: key == 'type' and value == 'example' and 'flip' in parent and 'flop' in parent):

        for element_y in select_element(data_two, lambda key, value, parent: key == 'flip' and value == element_y['flip']):
            element_x['flop'] = element_y['flop']