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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 atan(x, context=None):
 """ Return the inverse tangent of ``x``. The mathematically exact result lies in the range [-π/2, π/2]. However, note that as a result of rounding to the current context, it's possible for the actual value to lie just outside this range. """

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