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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 astype(self, dtype, undefined_on_failure=False):
 """ Create a new SArray with all values cast to the given type. Throws an exception if the types are not castable to the given type. Parameters dtype : {int, float, str, list, array.array, dict, datetime.datetime} The type to cast the elements to in SArray undefined_on_failure: bool, optional If set to True, runtime cast failures will be emitted as missing values rather than failing. Returns ------- out : SArray [dtype] The SArray converted to the type ``dtype``. Notes ----- - The string parsing techniques used to handle conversion to dictionary and list types are quite generic and permit a variety of interesting formats to be interpreted. For instance, a JSON string can usually be interpreted as a list or a dictionary type. See the examples below. - For datetime-to-string and string-to-datetime conversions, use sa.datetime_to_str() and sa.str_to_datetime() functions. - For array.array to turicreate.Image conversions, use sa.pixel_array_to_image() Examples -------- dtype: int Rows: 4 [1, 2, 3, 4] Given an SArray of strings that look like dicts, convert to a dictionary type: dtype: dict Rows: 2 [{1: 2, 3: 4}, {'a': 'b', 'c': 'd'}] """


        if (dtype == _Image) and (self.dtype == array.array):
            raise TypeError("Cannot cast from image type to array with sarray.astype(). Please use sarray.pixel_array_to_image() instead.")

        with cython_context():
            return SArray(_proxy=self.__proxy__.astype(dtype, undefined_on_failure))