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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 read_as_base64(fn):
 """ Convert given `fn` to base64 and return it. This method does the process in not-so-much memory consuming way. Args: fn (str):
 Path to the file which should be converted. Returns: str: File encoded as base64. """

    with open(fn) as unpacked_file:
        with tempfile.TemporaryFile() as b64_file:
            base64.encode(unpacked_file, b64_file)
            b64_file.flush()

            b64_file.seek(0)
            return b64_file.read()