Add new attribute into product catagory in magento and removing the same attribute

In any one of the .PHTML page paste the following code( i.e, app\design\frontend\base\default\template\page )
<?php

$setup = new Mage_Eav_Model_Entity_Setup('core_setup');

// Create input type as "Textbox"

$setup->addAttribute('catalog_category', 'author', array(
    'group'         => 'General',
    'input'         => 'text',
    'type'          => 'varchar',
    'label'         => 'Author',
    'backend'       => '',
    'visible'       => 1,
    'required'      => 0,
    'user_defined' => 1,
    'global'        => Mage_Catalog_Model_Resource_Eav_Attribute::SCOPE_GLOBAL,
));



// Create input type as " textarea "

$setup->addAttribute('catalog_category', 'author_description', array(
    'group'         => 'General',
    'input'         => 'textarea',
    'type'          => 'text',
    'label'         => 'Author_description',
    'backend'       => '',
    'visible'       => 1,
    'required'      => 0,
    'user_defined' => 1,
    'global'        => Mage_Catalog_Model_Resource_Eav_Attribute::SCOPE_GLOBAL,
));

// Create input type as " Dropdown list box"

$setup->addAttribute('catalog_category', 'vendors', array(
    'group'         => 'General',
    'input'         => 'select',
    'type'          => 'varchar',
    'label'         => 'Vendors',
    'backend'       => '',
    'visible'       => 1,
    'required'      => 0,
    'user_defined' => 1,
    'global'        => Mage_Catalog_Model_Resource_Eav_Attribute::SCOPE_GLOBAL,
    'option'            => array ('value' => array('optionone' => array('Sony'),'optiontwo' => array('Samsung'),
                                                       'optionthree' => array('Apple'),)),

));
?>

// Removing Attribute
<?php

$setup = new Mage_Eav_Model_Entity_Setup('core_setup');
$setup->removeAttribute('customer', 'customcode');

?>

Once the attribute is created in the admin panel, remove the above script from the PHTML.its safer