Write a function that converts an int num between 0-9 (inclusive) to its string equivalent (i.e., 1 -> "one").

def numToString(num):
  if num == 0:
    return 'zero'
  elif num == 1:
    return 'one'
  elif num == 2:
    return 'two'
  elif num == 3:
    return 'three'
  elif num == 4:
    return 'four'
  elif num == 5:
    return 'five'
  elif num == 6:
    return 'six'
  elif num == 7:
    return 'seven'
  elif num == 8:
    return 'eight'
  elif num == 9:
    return 'nine'
  else:
    return 'Not a valid number'