PyCERTSTORE = PFXImportCertStore(PFX, Password , Flags )
Creates a certificate store from PKCS#12 data (*.PFX files)
CommentsMSDN docs specify that *one* of the Flags can be used, but in practice a combination is allowed
Depending on the encrypting application, a blank password ("") may be treated differently that a NULL password (None), so if you have a PFX with no password try both.
Win32 API References