read_pdbstr in an API-only function which reads a pdb file from a Python string. This feature can be used to load or update structures into PyMOL without involving any temporary files.
PYMOL API ONLY
cmd.read_pdbstr( string pdb-content, string object name [ ,int state [ ,int finish [ ,int discrete ] ] ] )
state is a 1-based state index for the object.
finish is a flag (0 or 1) which can be set to zero to improve performance when loading large numbers of objects, but you must call "finish_object" when you are done.
discrete is a flag (0 or 1) which tells PyMOL that there will be no overlapping atoms in the PDB files being loaded. discrete objects save memory but can not be edited.