IndexError: index 39 is out of bounds for axis 0 with size 39

This error message indicates that you are trying to access an index that is out of the range of the array. In this specific case, the array has a size of 39 and you are trying to access the index 39, which is one more than the maximum index allowed for this array (since index values start at 0). To fix this error, you should check the size of your array and make sure that you are accessing only valid indices.