docs: def exists(Name, region=None, key=None, keyid=None, profile=None):
      '''
      Given a rule name, check to see if the given rule exists.
  
      Returns True if the given rule exists and returns False if the given
      rule does not exist.
  
      CLI example::
  
          salt myminion boto_cloudwatch_event.exists myevent region=us-east-1
      '''
      conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)
  
      try:
          events = conn.list_rules(NamePrefix=Name)
          if not events:
              return {'exists': False}
          for rule in events.get('Rules', []):
              if rule.get('Name', None) == Name:
                  return {'exists': True}
          return {'exists': False}
      except ClientError as e:
          err = __utils__['boto3.get_error'](e)
          return {'error': err}