text: # Licensed under a 3-clause BSD style license - see LICENSE.rst
  """
  .. _wcslib: https://www.atnf.csiro.au/people/mcalabre/WCS/wcslib/index.html
  .. _distortion paper: https://www.atnf.csiro.au/people/mcalabre/WCS/dcs_20040422.pdf
  .. _SIP: https://irsa.ipac.caltech.edu/data/SPITZER/docs/files/spitzer/shupeADASS.pdf
  .. _FITS WCS standard: https://fits.gsfc.nasa.gov/fits_wcs.html
  
  `astropy.wcs` contains utilities for managing World Coordinate System
  (WCS) transformations in FITS files.  These transformations map the
  pixel locations in an image to their real-world units, such as their
  position on the sky sphere.
  
  It performs three separate classes of WCS transformations:
  
  - Core WCS, as defined in the `FITS WCS standard`_, based on Mark
    Calabretta's `wcslib`_.  See `~astropy.wcs.Wcsprm`.
  - Simple Imaging Polynomial (`SIP`_) convention.  See
    `~astropy.wcs.Sip`.
  - table lookup distortions as defined in WCS `distortion paper`_.  See
    `~astropy.wcs.DistortionLookupTable`.
  
  Each of these transformations can be used independently or together in
  a standard pipeline.
  """
  
  from .wcs import *
  from .wcs import InvalidTabularParametersError  # just for docs
  from . import utils
  
  
  def get_include():
      """
      Get the path to astropy.wcs's C header files.
      """
      import os
      return os.path.join(os.path.dirname(__file__), "include")
  