'BalancedColumns' object has no attribute 'canv'

[fegamon]

I have this code:

F = [
    Paragraph(
        f'<b>Any text:</b> {foo}', style),
    Paragraph(f'<b>Another text:</b> {bar}', style2)
]

col_styles = {
    'leftPadding': 0,
    'rightPadding': 0,
    'topPadding': 0,
    'bottomPadding': 0,
}

a = BalancedColumns(F, 2, **col_styles)
print(a.wrap(self.doc.width, self.doc.height))

And I got the error : AttributeError: 'BalancedColumns' object has no attribute 'canv'