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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def smart_scrub(df,col_name,error_rate = 0):
 """ Scrubs from the front and back of an 'object' column in a DataFrame until the scrub would semantically alter the contents of the column. If only a subset of the elements in the column are scrubbed, then a boolean array indicating which elements have been scrubbed is appended to the dataframe. Returns a tuple of the strings removed from the front and back of the elements df - DataFrame DataFrame to scrub col_name - string Name of column to scrub error_rate - number, default 0 The maximum amount of values this function can ignore while scrubbing, expressed as a fraction of the total amount of rows in the dataframe. """

    scrubf = smart_scrubf(df,col_name,error_rate)
    scrubb = smart_scrubb(df,col_name,error_rate)
    return (scrubf, scrubb)