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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 write_pp_file(filename,pp_df):
 """write a pilot points dataframe to a pilot points file Parameters filename : str pilot points file to write pp_df : pandas.DataFrame a dataframe that has columns "x","y","zone", and "value" """

    with open(filename,'w') as f:
       f.write(pp_df.to_string(col_space=0,
                                columns=PP_NAMES,
                                formatters=PP_FMT,
                                justify="right",
                                header=False,
                                index=False) + '\n')