your model name is not a valid Java name! Help

Hi i want to add a 3d model to MCreator. I used a Blockbench. When import java file Mcreator show error. How can i decide problem

public class custom_model extends EntityModel<Entity> {
    private final ModelRenderer legs;
    private final ModelRenderer body;
    private final ModelRenderer head;
    private final ModelRenderer left_arm;
    private final ModelRenderer right_arm;

    public custom_model() {
        textureWidth = 64;
        textureHeight = 32;

        legs = new ModelRenderer(this);
        legs.setRotationPoint(0.0F, 8.0F, -3.0F);
        legs.setTextureOffset(0, 0).addBox(-1.0F, 9.0F, 0.0F, 1.0F, 6.0F, 3.0F, 0.0F, false);
        legs.setTextureOffset(0, 0).addBox(3.0F, 9.0F, 0.0F, 1.0F, 6.0F, 3.0F, 0.0F, false);
        legs.setTextureOffset(0, 0).addBox(1.0F, 9.0F, 0.0F, 1.0F, 6.0F, 3.0F, 0.0F, false);
        legs.setTextureOffset(0, 0).addBox(-5.0F, 9.0F, 0.0F, 1.0F, 6.0F, 3.0F, 0.0F, false);
        legs.setTextureOffset(0, 0).addBox(-3.0F, 9.0F, 0.0F, 1.0F, 6.0F, 3.0F, 0.0F, false);

        body = new ModelRenderer(this);
        body.setRotationPoint(0.0F, 24.0F, 0.0F);
        body.setTextureOffset(0, 0).addBox(-6.0F, -16.0F, -5.0F, 12.0F, 9.0F, 9.0F, 0.0F, false);

        head = new ModelRenderer(this);
        head.setRotationPoint(0.0F, 8.0F, -3.0F);
        head.setTextureOffset(0, 0).addBox(-3.0F, -5.0F, 0.0F, 6.0F, 5.0F, 5.0F, 0.0F, false);

        left_arm = new ModelRenderer(this);
        left_arm.setRotationPoint(0.0F, 24.0F, 0.0F);
        left_arm.setTextureOffset(0, 0).addBox(-9.0F, -15.0F, -2.0F, 2.0F, 10.0F, 3.0F, 0.0F, false);

        right_arm = new ModelRenderer(this);
        right_arm.setRotationPoint(-8.0F, -8.0F, 0.0F);
        left_arm.addChild(right_arm);
        right_arm.setTextureOffset(0, 0).addBox(14.0F, -7.0F, -2.0F, 2.0F, 10.0F, 3.0F, 0.0F, false);
    }

    @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){
        legs.render(matrixStack, buffer, packedLight, packedOverlay);
        body.render(matrixStack, buffer, packedLight, packedOverlay);
        head.render(matrixStack, buffer, packedLight, packedOverlay);
        left_arm.render(matrixStack, buffer, packedLight, packedOverlay);
    }

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