only integer scalar arrays can be converted to a scalar index

1. You attempted to perform array indexing on a list.

• List는 array indexing이 안 됨
  -> np.array(리스트) 로 numpy array로 만들어주자

2. You attempted to concatenate two matrices using incorrect syntax.

-> np.concatenate (mat1, mat2) (X)
-> np.concatenate ((mat1, mat2)) (X) (O)

https://www.statology.org/typeerror-only-integer-scalar-arrays-can-be-converted-to-scalar-index/