Struct and Enum in Unreal Engine python

struct_enum_unreal_engine_python.py

# Example by Filip Sivak, written for https://filipsivak.medium.com/
import unreal

@unreal.uenum()
class MyPythonEnum(unreal.EnumBase):
    FIRST = unreal.uvalue(0)
    SECOND = unreal.uvalue(1)
    FOURTH = unreal.uvalue(3)

@unreal.ustruct()
class PythonUnrealStruct(unreal.StructBase):
    some_string = unreal.uproperty(str)
    some_number = unreal.uproperty(float)
    array_of_string = unreal.uproperty(unreal.Array(str))

@unreal.uclass()
class PythonTestClass(unreal.BlueprintFunctionLibrary):

    @unreal.ufunction(static = True, params = [int], ret = PythonUnrealStruct)
    def MyPythonFunction(integer_argument1):
        struct = PythonUnrealStruct()
        struct.some_string = "5"
        struct.some_number = integer_argument1 + 1
        struct.array_of_string = ["a", "b", "c"]
        return struct

i made the PythonUnrealStruct as a variable in the blueprint ,but when i restarted the project .the variable would be removed or invalid,and then i need to recreate the variable. do you kown the reason and how can i make it useful all the time.thank you.

Yes, this is a typical error. Unfortunately, you need to run the python script creating the variable before use of the variable or on engine startup (in file init_unreal.py) and then recompile the blueprint.