write to csv file problem

[jacksfrustration]

i have the following function:

my_list=save_ent()
    new_list=[]

    for ent in my_list:
        new_list.append(output_found_flights(ent))
    try:
        data_file=pd.read_csv("flight_data.csv")
        data_dict=data_file.to_dict(orient="records")
    except pandas.errors.EmptyDataError:
        messagebox.showerror(title="Oooops",message="There are no saved information")
        data_dict=[]
    finally:
        for ent in new_list:
            data_dict.append(ent)
        try:
            for i,ent in enumerate(data_dict):
                res= not all (ent.values())
                if str(res):
                    data_dict.pop(i)
        except AttributeError:
            data_dict.pop(i)

        finally:

            new_data_file=pd.DataFrame(data_dict)
            new_data_file.to_csv("flight_data.csv",index=False)

the problem is the first time i run the code it executes correctly. When i try to add more search results it overwrites the csv file as expected but it gets rid of the previous search result and replaces it with the following

Output:
0
""