<*  Numpy 슬라이싱/인덱싱  *>

---< 예제 : Numpy_slicing_Indexing.py >--------------------------
import numpy as np
lst = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
]
arr = np.array(lst)
a = arr[0:2, 0:2]
print(a)
________________________________________________________________________
## [[1 2]
##  [4 5]]
a = arr[1:, 1:]
print(a)
## [[5 6]
##  [8 9]]