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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 _line_and_col_to_offset(lines, line, col):
 """Figure out the offset into a file for a particular line and col. This can return offsets that don't actually exist in the file. If you specify a line that exists and a col that is past the end of that line, this will return a "fake" offset. This is to account for the fact that a WorkItem's end_pos is one-past the end of a mutation, and hence potentially one-past the end of a file. Args: lines: A sequence of the lines in a file. line: A one-based index indicating the line in the file. col: A zero-based index indicating the column on `line`. Raises: ValueError: If the specified line found in the file. """


    offset = 0
    for index, contents in enumerate(lines, 1):
        if index == line:
            return offset + col

        offset += len(contents)

    raise ValueError("Offset {}:{} not found".format(line, col))