Fatal error when activating

Hi,

When I try to active Icegram, I’ve got this error message:
Fatal error: Can’t use function return value in write context in /var/www/my-domain/httpdocs/www/wp-content/plugins/icegram/icegram.php on line 1667

Line 1667 => $ig_survey_data[‘ig_plan’] = (!empty(get_option(‘ig_engage_plan’))) ? get_option(‘ig_engage_plan’) : false;

Could you please help me to fix that?
Thanks in advance.

Best regards.

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