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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 _memcopy(ins):
 """ Copies a block of memory from param 2 addr to param 1 addr. """

    output = _16bit_oper(ins.quad[3])
    output.append('ld b, h')
    output.append('ld c, l')
    output.extend(_16bit_oper(ins.quad[1], ins.quad[2], reversed=True))
    output.append('ldir')  # ***

    return output