Appending a variable to a list, howto? - "Error was can only concatenat e list (not \"unicode\") to list"}"

[Moshe_Suberri]

Error message: fatal: [localhost]: FAILED! => {“failed”: true, “msg”: “an unexpected type error occurred. Error was can only concatenate list (not "unicode") to list”}

Example:
my_list=
my_var=“var1”

my_list= mylist+my_var

final results:
my_List=[“var1”]

how do I do that?