You forgot the best part (I’m not sure there is an agreed-upon translation, so I’ll cite oremus randomly). The sentiment is repeated throughought the 10 plagues, but it’s most concise in chapter 10:

Pharaoh hurriedly summoned Moses and Aaron and said, ‘I have sinned against the Lord your God, and against you. Do forgive my sin […]’ […] The Lord changed the wind into a very strong west wind, which lifted the locusts and drove them into the Red Sea; not a single locust was left in all the country of Egypt. But the Lord hardened Pharaoh’s heart, and he would not let the Israelites go.