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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 sdram_free(self, ptr, x=Required, y=Required):
 """Free an allocated block of memory in SDRAM. .. note:: All unfreed SDRAM allocations associated with an application are automatically freed when the 'stop' signal is sent (e.g. after leaving a :py:meth:`.application` block). As such, this method is only useful when specific blocks are to be freed while retaining others. Parameters ptr : int Address of the block of memory to free. """

        self._send_scp(x, y, 0, SCPCommands.alloc_free,
                       consts.AllocOperations.free_sdram_by_ptr, ptr)