import matplotlib.pyplot as plt

import numpy as np

# Time or passage number

time $=$ np$.$linspace$(0,100,500)$

# Immortalized cell line $-$ exponential growth

immortalized$\_$yield $=$ np$.$exp$(0\mathrm{.}05*$ time$)$

# Non$-$immortalized cell line $-$ exponential growth followed by plateau and decline

primary$\_$yield $=$ np$.$piecewise$($time$,$

$[$time $<40,($time $>=40)$ & $($time $<70),$ time $>=70],$

$[$lambda x: np$.$exp$(0\mathrm{.}05*$ x$),$

lambda x: np$.$exp$(0\mathrm{.}05*40),$

lambda x: np$.$exp$(0\mathrm{.}0540)$ np$.$exp$(-0\mathrm{.}02*($x $-70))])$

plt$.$figure$($figsize$=(10,6))$

# Plotting the cell yield

plt$.$plot$($time$,$ immortalized$\_$yield, label$=$'Immortalized Cell Line', color$=$'blue'$)$

plt$.$plot$($time$,$ primary$\_$yield, label$=$'Non$-$Immortalized $($Primary$)$ Cell Line', color$=$'red'$)$

# Adding titles and labels

plt$.$title$(\text{'}$Total Cell Yield vs$.$ Time $($Passage Number$)\text{'})$

plt$.$xlabel$(\text{'}$Time $($Passage Number$)\text{'})$

plt$.$ylabel$(\text{'}$Total Cell Yield'$)$

plt$.$yscale$(\text{'}$log$\text{'})$ # Log scale to better visualize exponential growth

plt$.$legend$()$

plt$.$grid$($True$)$

plt$.$show$()$

dis code does not work what could be the problem. and fix it$.$