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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 label_both(label_info, multi_line=True, sep=': '):
 """ Concatenate the index and the value of the series. Parameters label_info : series Series whose values will be returned. It must have an index made of variable names. multi_line : bool Whether to place each variable on a separate line sep : str Separation between variable name and value Returns ------- out : series Label text strings """

    label_info = label_info.astype(str)
    for var in label_info.index:
        label_info[var] = '{0}{1}{2}'.format(var, sep, label_info[var])

    if not multi_line:
        label_info = collapse_label_lines(label_info)

    return label_info