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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 tolerant_equals(a, b, atol=10e-7, rtol=10e-7, equal_nan=False):
 """Check if a and b are equal with some tolerance. Parameters a, b : float The floats to check for equality. atol : float, optional The absolute tolerance. rtol : float, optional The relative tolerance. equal_nan : bool, optional Should NaN compare equal? See Also -------- numpy.isclose Notes ----- This function is just a scalar version of numpy.isclose for performance. See the docstring of ``isclose`` for more information about ``atol`` and ``rtol``. """

    if equal_nan and isnan(a) and isnan(b):
        return True
    return math.fabs(a - b) <= (atol + rtol * math.fabs(b))