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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 dropna(self, dim, how='any', thresh=None):
 """Returns a new array with dropped labels for missing values along the provided dimension. Parameters dim : str Dimension along which to drop missing values. Dropping along multiple dimensions simultaneously is not yet supported. how : {'any', 'all'}, optional * any : if any NA values are present, drop that label * all : if all values are NA, drop that label thresh : int, default None If supplied, require this many non-NA values. Returns ------- DataArray """

        ds = self._to_temp_dataset().dropna(dim, how=how, thresh=thresh)
        return self._from_temp_dataset(ds)