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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 profile_loglike(self, x):
 """Profile log-likelihood. Returns ``L_prof(x,y=y_min|z')`` : where y_min is the value of y that minimizes L for a given x. This will used the cached '~fermipy.castro.Interpolator' object if possible, and construct it if needed. """

        if self._prof_interp is None:
            # This calculates values and caches the spline
            return self._profile_loglike(x)[1]

        x = np.array(x, ndmin=1)
        return self._prof_interp(x)