docs: def check_requirements(to_populate, prompts, helper=False):
      '''
      Iterates through required values, checking to_populate for required values
  
      If a key in prompts is missing in to_populate and ``helper==True``,
      prompts the user using the values in to_populate. Otherwise, raises an
      error.
  
      Parameters
      ----------
  
      to_populate : dict
          Data dictionary to fill. Prompts given to the user are taken from this
          dictionary.
  
      prompts : dict
          Keys and prompts to use when filling ``to_populate``
      '''
  
      for kw, prompt in prompts.items():
          if helper:
              if kw not in to_populate:
                  to_populate[kw] = click.prompt(prompt)
          else:
              msg = (
                  'Required value "{}" not found. '
                  'Use helper=True or the --helper '
                  'flag for assistance.'.format(kw))
  
              assert kw in to_populate, msg