code: def fetch_rrlyrae_mags(data_home=None, download_if_missing=True):
      """Loader for RR-Lyrae data
  
      Parameters
      ----------
      data_home : optional, default=None
          Specify another download and cache folder for the datasets. By default
          all astroML data is stored in '~/astroML_data'.
  
      download_if_missing : optional, default=True
          If False, raise a IOError if the data is not locally available
          instead of trying to download the data from the source site.
  
      Returns
      -------
      data : recarray, shape = (483,)
          record array containing imaging data
  
      Examples
      --------
      >>> from astroML.datasets import fetch_rrlyrae_mags
      >>> data = fetch_rrlyrae_mags()  # doctest: +IGNORE_OUTPUT +REMOTE_DATA
      >>> # number of objects in dataset
      >>> data.shape  # doctest: +REMOTE_DATA
      (483,)
  
      Notes
      -----
      This data is from table 1 of Sesar et al 2010 ApJ 708:717
      """
      # fits is an optional dependency: don't import globally
      from astropy.io import fits
  
      data_home = get_data_home(data_home)
  
      archive_file = os.path.join(data_home, os.path.basename(DATA_URL))
  
      if not os.path.exists(archive_file):
          if not download_if_missing:
              raise IOError(
                  "data not present on disk. "
                  "set download_if_missing=True to download"
              )
  
          fitsdata = download_with_progress_bar(DATA_URL)
          open(archive_file, "wb").write(fitsdata)
  
      hdulist = fits.open(archive_file)
      return np.asarray(hdulist[1].data)
  
imports: import os
  import numpy
  from .None import get_data_home
  from .None import fetch_sdss_S82standards
  from .tools import download_with_progress_bar
label_desc: Use image node_id 1 for calling a global function with example usage: fetch_rrlyrae_mags(data_home, download_if_missing) and returns: np