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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 linecol_to_pos(text, line, col):
 """Return the offset of this line and column in text. Lines are one-based, columns zero-based. This is how Jedi wants it. Don't ask me why. """

    nth_newline_offset = 0
    for i in range(line - 1):
        new_offset = text.find("\n", nth_newline_offset)
        if new_offset < 0:
            raise ValueError("Text does not have {0} lines."
                             .format(line))
        nth_newline_offset = new_offset + 1
    offset = nth_newline_offset + col
    if offset > len(text):
        raise ValueError("Line {0} column {1} is not within the text"
                         .format(line, col))
    return offset