[Python] converting pine script to python

i am converting the following pine script to python. the python code works good but the last part of code which detects the dir/direction doesn't work.

//@version=4
study("STrend", overlay=true)

length = input(title="ATR Period", type=input.integer, defval=22)
mult = input(title="ATR Multiplier", type=input.float, step=0.1, defval=3)
src = input(title="Source", type=input.source, defval=hl2)
wicks = input(title="Take Wicks into Account ?", type=input.bool, defval=true)
showLabels = input(title="Show Buy/Sell Labels ?", type=input.bool, defval=true)
highlightState = input(title="Highlight State ?", type=input.bool, defval=true)

atr = mult * atr(length)
highPrice = wicks ? high : close
lowPrice = wicks ? low : close
doji4price = open == close and open == low and open == high

longStop = src - atr
longStopPrev = nz(longStop[1], longStop)
if longStop > 0
if doji4price
longStop := longStopPrev
else
longStop := (lowPrice[1] > longStopPrev ? max(longStop, longStopPrev) : longStop)
else
longStop := longStopPrev


shortStop = src + atr
shortStopPrev = nz(shortStop[1], shortStop)
if shortStop > 0
if doji4price
shortStop := shortStopPrev
else
shortStop := (highPrice[1] < shortStopPrev ? min(shortStop, shortStopPrev) : shortStop)
else
shortStop := shortStopPrev


var int dir = 1
dir :=
dir == -1 and highPrice > shortStopPrev ? 1 :
dir == 1 and lowPrice < longStopPrev ? -1 :
dir

plot(longStop, color=color.green)
plot(shortStop, color=color.red)
plotshape(dir == 1 ? dir: na, color=color.green)
plotshape(dir == -1 ? dir: na, color=color.red)


here is the python code which is converted from the above pine-script.

#!/usr/bin/env python3

import matplotlib.pyplot as plt
import pandas as pd
import pandas_ta as ta
import yfinance as yf


plt.style.use("fivethirtyeight")

df = yf.download("TSLA", start="2023-01-01")
print(df.head())

length = 22
mult = 3
df["hl2"] = (df["High"] + df["Low"]) / 2
src = df["hl2"]
atr = mult * ta.atr(df["High"], df["Low"], df["Close"], length=length)
doji4price = (
(df["Open"] == df["Close"]) & (df["Open"] == df["Low"]) & (df["Open"] == df["High"])
)

long_stop = src - atr
long_stop_prev = long_stop.shift(1).fillna(long_stop)
for i in range(1, len(long_stop)):
if long_stop > 0:
if doji4price:
long_stop = long_stop_prev
else:
long_stop = (
max(long_stop, long_stop_prev)
if df["Low"][i - 1] > long_stop_prev
else long_stop
)
else:
long_stop = long_stop_prev


short_stop = src + atr
short_stop_prev = short_stop.shift(1).fillna(short_stop)
for i in range(1, len(short_stop)):
if short_stop > 0:
if doji4price:
short_stop = short_stop_prev
else:
short_stop = (
min(short_stop, short_stop_prev)
if df["High"][i - 1] < short_stop_prev
else short_stop
)
else:
short_stop[i] = short_stop_prev[i]

d = 1
direction = []
for i in range(len(df)):
if d == -1 and df["High"][i] > short_stop_prev[i]:
d = 1
direction.append(1)
elif d == 1 and df["Low"][i] < long_stop_prev[i]:
d = -1
direction.append(-1)
else:
d = d
direction.append(d)

direction = pd.Series(direction)
direction.index = df.index


plt.plot(df["Close"], color="cyan")
plt.plot(long_stop, color="green")
plt.plot(short_stop, color="red")
plt.plot(df["Close"][direction == 1], "^", color="darkgreen")
plt.plot(df["Close"][direction == -1], "v", color="darkred")
plt.legend(["close", "long stop", "short stop", "^", "v"])
plt.show()


here is the [B]problem[/B]; the output of following python code is not same as the output of following pine script. from the month 1 to 7 the else part of the python code is executed which is wrong. look at the python plot and tradingview plot, the direction in python is not equal to the dir.

dir :=
dir == -1 and highPrice > shortStopPrev ? 1 :
dir == 1 and lowPrice < longStopPrev ? -1 :
dir


the python code in the below was written from the above pine-script but it's not doing the same thing. what's wrong with this part of the code?

d = 1
direction = []
for i in range(len(df)):
if d == -1 and df["High"][i] > short_stop_prev[i]:
d = 1
direction.append(1)
elif d == 1 and df["Low"][i] < long_stop_prev[i]:
d = -1
direction.append(-1)
else:
d = d
direction.append(d)


here is the plot of python code.

[URL='https://i.sstatic.net/Ucn9u.png'][IMG]https://i.sstatic.net/Ucn9u.png[/IMG][/URL]

and here is the plot of the tradingview pine script. the green line is longStop variable, red line is shortStop, green x is dir == 1 shows uptrend and red x shows downtrend dir == -1. the blue line is the close price.

[URL='https://i.sstatic.net/6mGGA.png'][IMG]https://i.sstatic.net/6mGGA.png[/IMG][/URL]

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