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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 _parse_tol(rtol,atol):
 """Parse the tolerance keywords"""

    #Process atol and rtol
    if rtol is None:
        rtol= -12.*nu.log(10.)
    else: #pragma: no cover
        rtol= nu.log(rtol)
    if atol is None:
        atol= -12.*nu.log(10.)
    else: #pragma: no cover
        atol= nu.log(atol)
    return (rtol,atol)