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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 GTFtoBED(inGTF,name):
 """ Transform a GTF dataframe into a bed dataframe :param inGTF: GTF dataframe for transformation :param name: field of the GTF data frame to be use for the bed 'name' positon returns: a bed dataframe with the corresponding bed fiels: 'chrom','chromStart','chromEnd','name','score','strand' """


    bed=inGTF.copy()
    bed.reset_index(inplace=True, drop=True)
    if name not in bed.columns.tolist():
        field=retrieve_GTF_field(name, bed)
        bed=pd.concat([bed,field],axis=1)
    bed=bed[['seqname','start','end',name,'score','strand']]
    bed.columns=['chrom','chromStart','chromEnd','name','score','strand']
    bed.drop_duplicates(inplace=True)
    bed.reset_index(inplace=True,drop=True)
    return bed