Senkou A (Leading Span A)

    Formula:
    (TenkanSen + KijunSen) / 2 :: Shift Forward 26 bars

def senkou_a(data):
    """
    Senkou A (Leading Span A)

    Formula:
    (TenkanSen + KijunSen) / 2 :: Shift Forward 26 bars
    """
    sa = (tenkansen(data) + kijunsen(data)) / 2
    # shift forward
    shift_by = np.repeat(np.nan, 26)
    sa = np.append(shift_by, sa)
    return sa