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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 is_label(token):
 """ Return whether the token is a label (an integer number or id at the beginning of a line. To do so, we compute find_column() and moves back to the beginning of the line if previous chars are spaces or tabs. If column 0 is reached, it's a label. """

    if not LABELS_ALLOWED:
        return False

    c = i = token.lexpos
    input = token.lexer.lexdata
    c -= 1
    while c > 0 and input[c] in (' ', '\t'):
        c -= 1

    while i > 0:
        if input[i] == '\n':
            break
        i -= 1

    column = c - i

    if column == 0:
        column += 1

    return column == 1