human
I am working on the file "Python/Chapter-06/Calculator-Frame.ipynb".
The first task is:
The function computeZero takes three arguments:
* s is a string that can be interpreted as a function $f$ of the variable x.
  For example, s could be equal to 'x * x - 2.0'.
* left and right are floating point numbers.
It is required that the function $f$ changes signs in the interval $[\texttt{left}, \texttt{right}]$.
Then computeZero returns a floating point value $x_0$ such that $f(x_0) \approx 0$.
Can you write Python program for it?
 Write me a the Python program you requested?
assistant
#Here is the Python program you requested.

def computeZero(s, left, right):
    TL = tokenize(s)

    def f(x):
        c = Calculator(TL, x)
        return c.evaluate()

    return findZero(f, left, right, 54);