Assign to this object the value of the specified rhs object, propagate to this object the allocator of rhs if the ALLOCATOR type has trait propagate_on_container_copy_assignment, and return a reference providing modifiable access to this object. If an exception is thrown, *this is left in a valid but unspecified state. This method requires that the (template parameter) type VALUE be copy‐assignable and copy‐insertable into this list. Note that, to the extent possible, existing elements of this list are copy‐assigned to, to minimize the number of nodes that need to be copy‐inserted or erased.