How to add Multires subdivide button to my own script As the title says, how do I add the subdivide button in the multires modifier to my own scripts. I managed to add the button but it does nothing when I press it.

Any help would be appreciated 

Edit: This the area of the script I'm having troubles with

import bpy

class CustomPanel(bpy.types.Panel):
    """A Custom Panel in the Viewport Toolbar"""
    bl_label = "MultiModifer"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS' 
    bl_category = "Sculpt"
    bl_category = "Tools"


    def draw(self, context):
        layout = self.layout

        row = layout.row()
        row.operator("object.multires_subdivide", text="Subdivide")
        row = layout.row()
        row.operator("object.multires_higher_levels_delete", text="Delete Higher")
        row = layout.row()
        row.label(text="Multires Levels")

        if(bpy.context.active_object.modifiers.find('Multires') != -1):
            layout.prop(context.object.modifiers["Multires"], "levels", text="Sculpt")

def register():
    bpy.utils.register_module(__name__)
def unregister():
    bpy.utils.unregister_module(__name__)

if __name__ == "__main__":
    register()
Pass parameters to layout.operator

The modifiers property panel is in "button context" and has a member context.modifier which the associated operators use.  In the 3d view toolbox there is no such context member, but we can pass the modifiers name to the operator.

Also rather than row after row, can use column layout.

import bpy

class CustomPanel(bpy.types.Panel):
    """A Custom Panel in the Viewport Toolbar"""
    bl_label = "MultiModifer"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS' 
    bl_category = "Sculpt"
    bl_category = "Tools"


    def draw(self, context):
        layout = self.layout
        obj = context.object
        mro = [m for m in obj.modifiers if m.type == 'MULTIRES']
        col = layout.column()
        for m in mro:                
            col.label(m.name)
            op = col.operator("object.multires_subdivide", text="Subdivide")
            op.modifier = m.name
            op = col.operator("object.multires_higher_levels_delete", text="Delete Higher")
            op.modifier = m.name
            col.label(text="Multires Levels")
            col.prop(m, "levels", text="Sculpt")

def register():
    bpy.utils.register_class(CustomPanel)

def unregister():
    bpy.utils.unregister_class(CustomPanel)

if __name__ == "__main__":
    register()