Help with importing java model

I created a simple seal model in blockbench and exported as a .java model but i keep getting the "your model name is not a valid java name!" error here is the code if that helps:

Also yes the file is just named custom_model.java

public class custom_model extends EntityModel<Entity> {
    

    public custom_model() {
        textureWidth = 16;
        textureHeight = 16;

        
    }

    @Override
    public void setRotationAngles(Entity entity, float limbSwing, float limbSwingAmount, float ageInTicks, float netHeadYaw, float headPitch){
        //previously the render function, render code was moved to a method below
    }

    @Override
    public void render(MatrixStack matrixStack, IVertexBuilder buffer, int packedLight, int packedOverlay, float red, float green, float blue, float alpha){
        
    }

    public void setRotationAngle(ModelRenderer modelRenderer, float x, float y, float z) {
        modelRenderer.rotateAngleX = x;
        modelRenderer.rotateAngleY = y;
        modelRenderer.rotateAngleZ = z;
    }
}