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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 pos(x, context=None):
 """ Return ``x``. As usual, the result is rounded to the current context. The ``pos`` function can be useful for rounding an intermediate result, computed with a temporary increase in precision, back to the current context. For example:: BigFloat.exact('1.2340002059936523', precision=53) BigFloat.exact('1.2339999999999999857891452847980', precision=100) BigFloat.exact('1.2340000000000000', precision=53) """

    return _apply_function_in_current_context(
        BigFloat,
        mpfr.mpfr_set,
        (BigFloat._implicit_convert(x),),
        context,
    )