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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_fasta(fasta_file, output_dict):
 """ Read the peptide fasta into an existing dict. :param str fasta_file: The peptide file :param dict output_dict: The dict to appends results to. :return: output_dict :rtype: dict """

    read_name = None
    with open(fasta_file, 'r') as f:
        for line in f:
            line = line.strip()
            if not line:
                continue
            if line.startswith('>'):
                read_name = line.lstrip('>')
            else:
                assert read_name is not None, line
                output_dict[read_name].append(line.strip())
    return output_dict