Create a method that evaluates a mathematical expression from a string, respecting the order of operations (PEMDAS/BODMAS). The expression will only contain integers, addition (+), subtraction (-), multiplication (*), and division (/).

Examples:

Input: expression = "3 + 5 * 2"
Output: 13
Explanation: Multiplication is performed before addition (5 * 2 = 10, then 3 + 10 = 13).

Input: expression = "10 - 8 / 2"
Output: 6
Explanation: Division is performed before subtraction (8 / 2 = 4, then 10 - 4 = 6).

Input: expression = "2 * (3 + 4) - 5"
Output: 9
Explanation: Operations in parentheses are performed first (3 + 4 = 7), then multiplication (2 * 7 = 14), and finally subtraction (14 - 5 = 9).
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