Finding positive peaks of function

It is necessary to programmatically find the number and location of positive peaks on the graph.
It is known that the number of peaks is odd. Typically, 3, 5 or 7. In this case, 3. It is also known that each positive peak is followed by a negative one.
What is the best way to solve such a problem in Python? Preferably without selecting
coefficients : the data always starts with a positive peak and ends with a negative one.
The data is the vertical projection of an image processed with the function np.gradient(projection)/projection . That is, the ratio of the second derivative of the function to its height.