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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 get_window_size(window):
 """ Retrieves the size of the client area of the specified window. Wrapper for: void glfwGetWindowSize(GLFWwindow* window, int* width, int* height); """

    width_value = ctypes.c_int(0)
    width = ctypes.pointer(width_value)
    height_value = ctypes.c_int(0)
    height = ctypes.pointer(height_value)
    _glfw.glfwGetWindowSize(window, width, height)
    return width_value.value, height_value.value