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composer require tomaskarlik/dateinputRegister extension in config.neon
dateinput: TomasKarlik\DateInput\DateInputExtensionUsage
$form->addDate('dateTo', 'Datum do:')
	->setRequired('Zadejte datum do!')
	->addRule(Form::VALID, 'Zadejte platné datum!')
	->setAttribute('class', 'datepicker');
$form->addDate('date', 'Date:', 'Y-m-d')
	->setRequired(FALSE)
	->addRule(Form::VALID)
	->setDefaultValue(new DateTime);