# outlier detection function
def outlier(col:str, df_:pd.DataFrame=df, remove:bool=False) -> list:
"""This function calculates the upper and lower fence
of any column and can also remove from the dataset"""
q1 = df_[col].quantile(0.25)
q3 = df_[col].quantile(0.75)
iqr = q3-q1
lower_fence = q1 - iqr*1.5
upper_fence = q3 + iqr*1.5
if remove:
temp = df_[(df_[col] > lower_fence) & (df_[col] < upper_fence)]
return temp
return [lower_fence, upper_fence]