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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 make_idx(f, lb, ub):
 """ This is a little utility function to replace an oft-called set of operations Parameters f : 1d array A frequency axis along which we want to slice lb : float Defines the upper bound of slicing ub : float Defines the lower bound of slicing Returns ------- idx : a slice object """

    
    idx0 = np.argmin(np.abs(f - lb))
    idx1 = np.argmin(np.abs(f - ub))

    # Determine which should be on which side
    if f[0] > f[1]:
        direction = -1
    else:
        direction = 1
        
    if direction == -1:
        idx = slice(idx1, idx0)
    elif direction == 1:
        idx = slice(idx0, idx1)

    return idx