input: Write a python function to recode ages in a DataFrame based on whether they are above or below 30.
  assert recode_age(pd.DataFrame({'age': [25, 35, 30, 40]})).equals(pd.DataFrame({'age': [25, 35, 30, 40], 'age_recoded': ['Below 30', 'Above 30', 'Below 30', 'Above 30']}))
  assert recode_age(pd.DataFrame({'age': [20, 50, 29]})).equals(pd.DataFrame({'age': [20, 50, 29], 'age_recoded': ['Below 30', 'Above 30', 'Below 30']}))
  assert recode_age(pd.DataFrame({'age': [30, 31, 28]})).equals(pd.DataFrame({'age': [30, 31, 28], 'age_recoded': ['Below 30', 'Above 30', 'Below 30']}))
output: def recode_age(df):
      df['age_recoded'] = df['age'].apply(lambda x: 'Above 30' if x > 30 else 'Below 30')
      return df