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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_array(self, dim='variable', name=None):
 """Convert this dataset into an xarray.DataArray The data variables of this dataset will be broadcast against each other and stacked along the first axis of the new array. All coordinates of this dataset will remain coordinates. Parameters dim : str, optional Name of the new dimension. name : str, optional Name of the new data array. Returns ------- array : xarray.DataArray """

        from .dataarray import DataArray

        data_vars = [self.variables[k] for k in self.data_vars]
        broadcast_vars = broadcast_variables(*data_vars)
        data = duck_array_ops.stack([b.data for b in broadcast_vars], axis=0)

        coords = dict(self.coords)
        coords[dim] = list(self.data_vars)

        dims = (dim,) + broadcast_vars[0].dims

        return DataArray(data, coords, dims, attrs=self.attrs, name=name)