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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 append_little_endian32(self, unsigned_value):
 """Appends an unsigned 32-bit integer to the internal buffer, in little-endian byte order. """

        if not 0 <= unsigned_value <= wire_format.UINT32_MAX:
            raise errors.EncodeError(
                'Unsigned 32-bit out of range: %d' % unsigned_value)
        self.append_raw_bytes(struct.pack(
            wire_format.FORMAT_UINT32_LITTLE_ENDIAN, unsigned_value))