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Given the following text problem statement, write Python code to implement the functionality described below in problem statement
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Problem:
In pandas, how do I replace &AMP; with '&' from all columns where &AMP could be in any position in a string?
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Python Code:
import pandas as pd
df = pd.DataFrame({'A': ['Good &AMP; bad', 'BB', 'CC', 'DD', 'Good &AMP; bad'], 'B': range(5), 'C': ['Good &AMP; bad'] * 5})
def g(df):
    return df.replace('&AMP;','&', regex=True)
df = g(df.copy())
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