Regular expression to character being repeated more than 1 times

I have dataframe with column ‘code’:

import pandas as pd
df = pd.DataFrame({'code': ['10SGD01AA103||||||10SGD01AA105||||||10SGD01AA111']})

How can I drop repeated character ‘|’ and leave only one.

10SGD01AA103|10SGD01AA105|10SGD01AA111

I use str.replace:

df['code'] = df['code'].str.replace('|(?=|1+)', '', regex=True)

or

df['code'] = df['code'].str.replace('|(?=|)', '', regex=True)

But repeated character does not drop.