Inserts all the specified values at the head of the list stored at key. If key does not exist, it is created as empty list before performing the push operations.
|key holding the list to left push to.
|a variadic array of strings, numbers, or booleans
|values to push to the list.
|On success, the promise resolves with the length of the list after the push.
|When key holds a value that is not a list, the promise is rejected with an error.