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# Source code for astropy.nddata.mixins.ndio

    # Licensed under a 3-clause BSD style license - see LICENSE.rst
    # This module implements the I/O mixin to the NDData class.

    from astropy.io import registry

    __all__ = ["NDIOMixin"]
    __doctest_skip__ = ["NDDataRead", "NDDataWrite"]

    class NDDataRead(registry.UnifiedReadWrite):
        """Read and parse gridded N-dimensional data and return as an NDData-derived
        object.

        This function provides the NDDataBase interface to the astropy unified I/O
        layer.  This allows easily reading a file in the supported data formats,
        for example::

          >>> from astropy.nddata import CCDData
          >>> dat = CCDData.read('image.fits')

        Get help on the available readers for ``CCDData`` using the``help()`` method::

          >>> CCDData.read.help()  # Get help reading CCDData and list supported formats
          >>> CCDData.read.help('fits')  # Get detailed help on CCDData FITS reader
          >>> CCDData.read.list_formats()  # Print list of available formats

        See also:

        - https://docs.astropy.org/en/stable/nddata
        - https://docs.astropy.org/en/stable/io/unified.html

        Parameters
        ----------
        *args : tuple, optional
            Positional arguments passed through to data reader. If supplied the
            first argument is the input filename.
        format : str, optional
            File format specifier.
        cache : bool, optional
            Caching behavior if file is a URL.
        **kwargs : dict, optional
            Keyword arguments passed through to data reader.

        Returns
        -------
        out : `NDData` subclass
            NDData-basd object corresponding to file contents

        Notes
        -----
        """

        def __init__(self, instance, cls):
            super().__init__(instance, cls, "read", registry=None)
            # uses default global registry

        def __call__(self, *args, **kwargs):
            return self.registry.read(self._cls, *args, **kwargs)

    class NDDataWrite(registry.UnifiedReadWrite):
        """Write this CCDData object out in the specified format.

        This function provides the NDData interface to the astropy unified I/O
        layer.  This allows easily writing a file in many supported data formats
        using syntax such as::

          >>> from astropy.nddata import CCDData
          >>> dat = CCDData(np.zeros((12, 12)), unit='adu')  # 12x12 image of zeros
          >>> dat.write('zeros.fits')

        Get help on the available writers for ``CCDData`` using the``help()`` method::

          >>> CCDData.write.help()  # Get help writing CCDData and list supported formats
          >>> CCDData.write.help('fits')  # Get detailed help on CCDData FITS writer
          >>> CCDData.write.list_formats()  # Print list of available formats

        See also:

        - https://docs.astropy.org/en/stable/nddata
        - https://docs.astropy.org/en/stable/io/unified.html

        Parameters
        ----------
        *args : tuple, optional
            Positional arguments passed through to data writer. If supplied the
            first argument is the output filename.
        format : str, optional
            File format specifier.
        **kwargs : dict, optional
            Keyword arguments passed through to data writer.

        Notes
        -----
        """

        def __init__(self, instance, cls):
            super().__init__(instance, cls, "write", registry=None)
            # uses default global registry

        def __call__(self, *args, **kwargs):
            self.registry.write(self._instance, *args, **kwargs)

    class NDIOMixin:
        """
        Mixin class to connect NDData to the astropy input/output registry.

        This mixin adds two methods to its subclasses, ``read`` and ``write``.
        """

        read = registry.UnifiedReadWriteMethod(NDDataRead)
        write = registry.UnifiedReadWriteMethod(NDDataWrite)