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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 _read_generic_csv(file):
 """ Read and parse generic CSV file. Notes ----- Assumes columns are 'rsid', 'chrom' / 'chromosome', 'pos' / 'position', and 'genotype'; values are comma separated; unreported genotypes are indicated by '--'; and one header row precedes data. For example: rsid,chromosome,position,genotype rs1,1,1,AA rs2,1,2,CC rs3,1,3,-- Parameters file : str path to file Returns ------- pandas.DataFrame individual's genetic data normalized for use with `lineage` str name of data source """

        df = pd.read_csv(
            file,
            skiprows=1,
            na_values="--",
            names=["rsid", "chrom", "pos", "genotype"],
            index_col=0,
            dtype={"chrom": object, "pos": np.int64},
        )

        return sort_snps(df), "generic"