If a gganimintproto object has a $print method, this will call that method.
Otherwise, it will print out the members of the object, and optionally, the
members of the inherited objects.
# S3 method for gganimintproto
print(x, ..., flat = TRUE)A gganimintproto object to print.
If the gganimintproto object has a print method, further arguments
will be passed to it. Otherwise, these arguments are unused.
If TRUE (the default), show a flattened list of all local
and inherited members. If FALSE, show the inheritance hierarchy.