How to use the pygmt.helpers.dummy_context function in pygmt

Returns
    -------
    ret: xarray.DataArray or None
        Return type depends on whether the outfile (G) parameter is set:

        - xarray.DataArray if outfile (G) is not set
        - None if outfile (G) is set (grid output will be stored in outfile)
    """
    kind = data_kind(data, x, y, z)
    if kind == "vectors" and z is None:
        raise GMTInvalidInput("Must provide z with x and y.")

    with GMTTempFile(suffix=".nc") as tmpfile:
        with Session() as lib:
            if kind == "file":
                file_context = dummy_context(data)
            elif kind == "matrix":
                file_context = lib.virtualfile_from_matrix(data)
            elif kind == "vectors":
                file_context = lib.virtualfile_from_vectors(x, y, z)
            else:
                raise GMTInvalidInput("Unrecognized data type: {}".format(type(data)))
            with file_context as infile:
                if "G" not in kwargs.keys():  # if outfile is unset, output to tmpfile
                    kwargs.update({"G": tmpfile.name})
                outfile = kwargs["G"]
                arg_str = " ".join([infile, build_arg_string(kwargs)])
                lib.call_module(module="surface", args=arg_str)

        if outfile == tmpfile.name:  # if user did not set outfile, return DataArray
            with xr.open_dataset(outfile) as dataset:
                result = dataset.load()

Full option list at :gmt-docs:`grdimage.html`

        {aliases}

        Parameters
        ----------
        grid : str or xarray.DataArray
            The file name of the input grid or the grid loaded as a DataArray.

        """
        kwargs = self._preprocess(**kwargs)
        kind = data_kind(grid, None, None)
        with Session() as lib:
            if kind == "file":
                file_context = dummy_context(grid)
            elif kind == "grid":
                file_context = lib.virtualfile_from_grid(grid)
            else:
                raise GMTInvalidInput("Unrecognized data type: {}".format(type(grid)))
            with file_context as fname:
                arg_str = " ".join([fname, build_arg_string(kwargs)])
                lib.call_module("grdimage", arg_str)

raise GMTInvalidInput(
                    "Can't use arrays for color if data is matrix or file."
                )
            extra_arrays.append(kwargs["G"])
            del kwargs["G"]
        if sizes is not None:
            if kind != "vectors":
                raise GMTInvalidInput(
                    "Can't use arrays for sizes if data is matrix or file."
                )
            extra_arrays.append(sizes)

        with Session() as lib:
            # Choose how data will be passed in to the module
            if kind == "file":
                file_context = dummy_context(data)
            elif kind == "matrix":
                file_context = lib.virtualfile_from_matrix(data)
            elif kind == "vectors":
                file_context = lib.virtualfile_from_vectors(
                    np.atleast_1d(x), np.atleast_1d(y), *extra_arrays
                )

            with file_context as fname:
                arg_str = " ".join([fname, build_arg_string(kwargs)])
                lib.call_module("plot", arg_str)

``'[low]/[high]'``  or list ``[low,high]``.
        Q : string or int
            Do not draw contours with less than `cut` number of points.
        S : string or int
            Resample smoothing factor.
        {J}
        {R}
        {B}
        {G}
        {W}
        """
        kwargs = self._preprocess(**kwargs)
        kind = data_kind(grid, None, None)
        with Session() as lib:
            if kind == "file":
                file_context = dummy_context(grid)
            elif kind == "grid":
                file_context = lib.virtualfile_from_grid(grid)
            else:
                raise GMTInvalidInput("Unrecognized data type: {}".format(type(grid)))
            with file_context as fname:
                arg_str = " ".join([fname, build_arg_string(kwargs)])
                lib.call_module("grdcontour", arg_str)

{W}
        X : Origin shift x
        Y : Origin shift y


        """
        kwargs = self._preprocess(**kwargs)

        kind = data_kind(data, x, y, z)
        if kind == "vectors" and z is None:
            raise GMTInvalidInput("Must provided both x, y, and z.")

        with Session() as lib:
            # Choose how data will be passed in to the module
            if kind == "file":
                file_context = dummy_context(data)
            elif kind == "matrix":
                file_context = lib.virtualfile_from_matrix(data)
            elif kind == "vectors":
                file_context = lib.virtualfile_from_vectors(x, y, z)

            with file_context as fname:
                arg_str = " ".join([fname, build_arg_string(kwargs)])
                lib.call_module("contour", arg_str)

Parameters
    ----------
    grid : str or xarray.DataArray
        The file name of the input grid or the grid loaded as a DataArray.

    Returns
    -------
    info : str
        A string with information about the grid.

    """
    kind = data_kind(grid, None, None)
    with GMTTempFile() as outfile:
        with Session() as lib:
            if kind == "file":
                file_context = dummy_context(grid)
            elif kind == "grid":
                file_context = lib.virtualfile_from_grid(grid)
            else:
                raise GMTInvalidInput("Unrecognized data type: {}".format(type(grid)))
            with file_context as infile:
                arg_str = " ".join(
                    [infile, build_arg_string(kwargs), "->" + outfile.name]
                )
                lib.call_module("grdinfo", arg_str)
        result = outfile.read()
    return result