Let \( F = \{\omega \in \mathbb{C} : \omega^{2020} = 1\}. \)
Consider the groups \[ G = \left\{ \begin{pmatrix} \omega & z \\ 0 & 1 \end{pmatrix} : \omega \in F, z \in \mathbb{C} \right\} \text{and} H = \left\{ \begin{pmatrix} 1 & z \\ 0 & 1 \end{pmatrix} : z \in \mathbb{C} \right\} \] under matrix multiplication.
Then the number of cosets of \( H \) in \( G \) is