Could you please be more specific as to which operation exactly you mean?

If you mean the "redo last" operation, which I believe is the default key binding for this function, then you can use this: (note that you'll have to include bl_info and register and unregister functions as in the code snippet below )

import bpy

class redo_last_operator(bpy.types.Operator):
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

Please note that importing this as an add-on will only add the operator to Blender, not add a Button to any panel. You can do that yourself, however, by creating a panel for it or adding it to a Panel yourself. The following code will create a panel as well:

import bpy

bl_info = {
    "version": (1, 0),
    "blender": (2, 75, 0),
    "name": "Redo Last Operator",
    "description": """Creates an operator for the redo last menu""" ,
    "category": "File",
    "location": """""",
}

class redo_last_operator(bpy.types.Operator):
    # this class is meant only for destroying data blocks of a certain type, very powerful but very dangerous
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

class redo_last_operator_panel(bpy.types.Panel):
    bl_label="redo last"
    bl_idname="redo_last_operator"
    bl_space_type = "VIEW_3D"
    bl_region_type = "TOOLS"
    bl_category='Addons'

    def draw(self,context):
        self.layout.operator(redo_last_operator.bl_idname)

def register():
    bpy.utils.register_class(redo_last_operator)
    bpy.utils.register_class(redo_last_operator_panel)

def unregister():
    bpy.utils.unregister_class(redo_last_operator)
    bpy.utils.unregister_class(redo_last_operator_panel)

if __name__ == "__main__":
    register()

If, on the other hand, you meant another operation, you can use the same code and still bind it to the button by replacing the code under execute().

I notice that your question says "call a panel"; what exactly did you mean with this?

If you mean the "redo last" operation, which I believe is the default key binding for this function, then you can use this: (note that you'll have to include bl_info and register and unregister functions as in the code snippet below )

import bpy

class redo_last_operator(bpy.types.Operator):
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

Please note that importing this as an add-on will only add the operator to Blender, not add a Button to any panel. You can do that yourself, however, by creating a panel for it or adding it to a Panel yourself. The following code will create a panel as well:

import bpy

bl_info = {
    "version": (1, 0),
    "blender": (2, 75, 0),
    "name": "Redo Last Operator",
    "description": """Creates an operator for the redo last menu""" ,
    "category": "File",
    "location": """""",
}

class redo_last_operator(bpy.types.Operator):
    # this class is meant only for destroying data blocks of a certain type, very powerful but very dangerous
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

class redo_last_operator_panel(bpy.types.Panel):
    bl_label="redo last"
    bl_idname="redo_last_operator"
    bl_space_type = "VIEW_3D"
    bl_region_type = "TOOLS"
    bl_category='Addons'

    def draw(self,context):
        self.layout.operator(redo_last_operator.bl_idname)

def register():
    bpy.utils.register_class(redo_last_operator)
    bpy.utils.register_class(redo_last_operator_panel)

def unregister():
    bpy.utils.unregister_class(redo_last_operator)
    bpy.utils.unregister_class(redo_last_operator_panel)

if __name__ == "__main__":
    register()

If, on the other hand, you meant another operation, you can use the same code and still bind it to the button by replacing the code under execute().

Could you please be more specific as to which operation exactly you mean?

If you mean the "redo last" operation, which I believe is the default key binding for this function, then you can use this: (note that you'll have to include bl_info and register and unregister functions as in the code snippet below )

import bpy

class redo_last_operator(bpy.types.Operator):
    bl_idname = "screen.redo_last"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

Please note that importing this as an add-on will only add the operator to Blender, not add a Button to any panel. You can do that yourself, however, by creating a panel for it or adding it to a Panel yourself. The following code will create a panel as well:

import bpy

bl_info = {
    "version": (1, 0),
    "blender": (2, 75, 0),
    "name": "Redo Last Operator",
    "description": """Creates an operator for the redo last menu""" ,
    "category": "File",
    "location": """""",
}

class redo_last_operator(bpy.types.Operator):
    # this class is meant only for destroying data blocks of a certain type, very powerful but very dangerous
    bl_idname = "screen.redo_last"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

class redo_last_operator_panel(bpy.types.Panel):
    bl_label="redo last"
    bl_idname="redo_last_operator"
    bl_space_type = "VIEW_3D"
    bl_region_type = "TOOLS"
    bl_category='Addons'

    def draw(self,context):
        self.layout.operator(redo_last_operator.bl_idname)

def register():
    bpy.utils.register_class(redo_last_operator)
    bpy.utils.register_class(redo_last_operator_panel)

def unregister():
    bpy.utils.unregister_class(redo_last_operator)
    bpy.utils.unregister_class(redo_last_operator_panel)

if __name__ == "__main__":
    register()

If, on the other hand, you meant another operation, you can use the same code and still bind it to the button by replacing the code under execute().

I notice that your question says "call a panel"; what exactly did you mean with this?

Could you please be more specific as to which operation exactly you mean?

If you mean the "redo last" operation, which I believe is the default key binding for this function, then you can use this: (note that you'll have to include bl_info and register and unregister functions as in the code snippet below )

import bpy

class redo_last_operator(bpy.types.Operator):
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

Please note that importing this as an add-on will only add the operator to Blender, not add a Button to any panel. You can do that yourself, however, by creating a panel for it or adding it to a Panel yourself. The following code will create a panel as well:

import bpy

bl_info = {
    "version": (1, 0),
    "blender": (2, 75, 0),
    "name": "Redo Last Operator",
    "description": """Creates an operator for the redo last menu""" ,
    "category": "File",
    "location": """""",
}

class redo_last_operator(bpy.types.Operator):
    # this class is meant only for destroying data blocks of a certain type, very powerful but very dangerous
    bl_idname = "screen.redo_last_operator"
    bl_label = "redo last"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self,context):
        bpy.ops.screen.redo_last()
        return {'FINISHED'}

class redo_last_operator_panel(bpy.types.Panel):
    bl_label="redo last"
    bl_idname="redo_last_operator"
    bl_space_type = "VIEW_3D"
    bl_region_type = "TOOLS"
    bl_category='Addons'

    def draw(self,context):
        self.layout.operator(redo_last_operator.bl_idname)

def register():
    bpy.utils.register_class(redo_last_operator)
    bpy.utils.register_class(redo_last_operator_panel)

def unregister():
    bpy.utils.unregister_class(redo_last_operator)
    bpy.utils.unregister_class(redo_last_operator_panel)

if __name__ == "__main__":
    register()

If, on the other hand, you meant another operation, you can use the same code and still bind it to the button by replacing the code under execute().

I notice that your question says "call a panel"; what exactly did you mean with this?