Read the source code for Packages

// general format
SELECT *
FROM
user_source
WHERE rownum <10;

// Find the source for Method INV_LOT_API_PUB specification
SELECT *
FROM
user_source
WHERE NAME='INV_LOT_API_PUB';

// Get the types within Package Specification
SELECT *
FROM
user_source
WHERE NAME='INV_LOT_API_PUB'
AND
TEXT LIKE (' TYPE%');