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add_filter( 'woocommerce_loop_add_to_cart_link', 'quantity_inputs_for_woocommerce_loop_add_to_cart_link', 10, 2 );
function quantity_inputs_for_woocommerce_loop_add_to_cart_link( $html, $product ) {
	global $product;
	if ( $product && $product->is_type( 'simple' ) && $product->is_purchasable() && $product->is_in_stock() && ! $product->is_sold_individually() ) {
		$html = '<form action="' . esc_url( $product->add_to_cart_url() ) . '" class="cart" method="post" enctype="multipart/form-data">';
		$html .= woocommerce_quantity_input( array(), $product, false );
		$html .=  sprintf( '<a rel="nofollow" href="%s" data-quantity="%s" data-product_id="%s" data-product_sku="%s" class="%s">%s</a>',
			esc_url( $product->add_to_cart_url() ),
			esc_attr( isset( $quantity ) ? $quantity : 1 ),
			esc_attr( $product->get_id() ),
			esc_attr( $product->get_sku() ),
			esc_attr('button ajax_add_to_cart add_to_cart_button product_type_simple' ),
			esc_html( $product->add_to_cart_text() )
		);
		$html .= '</form>';
	}
	return $html;
}