Mistake in backpropagation

[eatam23]

Location
Please provide:

1. Version (bottom left page): July 2022 version
2. Page number: 142
3. Line/equation number: Eq. (6.22)

Describe the mistake
$U^{(l)}$ in partial derivatives should be $U_{l}$ because it was described like this before (see page 137)

Suggested change
$U^{(l)}$ in partial derivatives should be $U_{l}$ because it was described like this before (see page 137)

Additional comments