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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 get_file(self, cache_id_obj, section=None):
 """Returns the file path for the given cache object."""

        section = "default" if section is None else section
        if "/" in section:
            raise ValueError("invalid section '{0}'".format(section))
        cache_id = "{:08x}".format(
            zlib.crc32(b"&".join(sorted([
                str(k).encode('utf8') + b"=" + str(v).encode('utf8')
                for k, v in cache_id_obj.items()
            ]))) & 0xffffffff)
        return os.path.join(self._full_base,
                            os.path.join(section,
                                         os.path.join(
                                             "{0}".format(cache_id[:2]),
                                             "{0}.tmp".format(cache_id[2:]))))