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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 add_header(self, entry):
 """Parses the VCF Header field and returns the number of samples in the VCF file"""

        info = entry.split('\t')
        self.n_individuals = len(info)-9
        for i,v in enumerate(info[9:]):
            self.individuals[v] = i
        return self.n_individuals > 0