error on stock indicator code on balance volume

[gontajones]

Do you need the OBV_1 column inside the on_balance_volume()?
Because it is being added only at the end of the function.

Here, after the on_balance_volume(), it is there:

aapl = on_balance_volume(aapl, n)
print(aapl.index)
print(aapl.columns)
print(aapl['OBV_1'])

Output:
RangeIndex(start=0, stop=17, step=1)
Index(['Date', 'Open', 'High', 'Low', 'Close', 'Adj Close', 'Volume', 'OBV_1'], dtype='object')
0             0.0
1      88102700.0
2     123432400.0
3    -138040000.0
4    -119282800.0
5     119282800.0
6    -115557400.0
7    -148614900.0
8     148614900.0
9    -108223500.0
10   -148516900.0
11    148516900.0
12   -153038200.0
13   -152038600.0
14   -220441900.0
15    220441900.0
16    266424900.0
Name: OBV_1, dtype: float64