List of all Python 3.7 modules that comes preinstalled in vRealize Orchestrator 8.x for quick reference:

__future___warningsgziprunpy
_abc_weakrefhashlibsched
_ast_weakrefsetheapqsecrets
_asyncio_xxtestfuzzhmacselect
_bisectabchtmlselectors
_blake2aifchttpshelve
_bootlocaleantigravityidlelibshlex
_bz2argparseimaplibshutil
_codecsarrayimghdrsignal
_codecs_cnastimpsite
_codecs_hkasynchatimportlibsmtpd
_codecs_iso2022asyncioindexsmtplib
_codecs_jpasyncoreinspectsndhdr
_codecs_kratexitiosocket
_codecs_twaudioopipaddresssocketserver
_collectionsbase64itertoolsspwd
_collections_abcbdbjsonsqlite3
_compat_picklebinasciikeywordsre_compile
_compressionbinhexlib2to3sre_constants
_contextvarsbisectlinecachesre_parse
_cryptbuiltinslocalessl
_csvbz2loggingstat
_ctypescProfilelzmastatistics
_datetimecalendarmacpathstring
_decimalcgimailboxstringprep
_dummy_threadcgitbmailcapstruct
_elementtreechunkmarshalsubprocess
_functoolscmathmathsunau
_hashlibcmdmimetypessymbol
_heapqcodemmapsymtable
_impcodecsmodulefindersys
_iocodeopmultiprocessingsysconfig
_jsoncollectionsnetrcsyslog
_localecolorsysnntplibtabnanny
_lsprofcompileallntpathtarfile
_lzmaconcurrentnturl2pathtelnetlib
_markupbaseconfigparsernumberstempfile
_md5contextlibopcodetermios
_multibytecodeccontextvarsoperatortextwrap
_multiprocessingcopyoptparsethis
_opcodecopyregosthreading
_operatorcryptossaudiodevtime
_osx_supportcsvparsertimeit
_picklectypespathlibtkinter
_posixsubprocessdataclassespdbtoken
_py_abcdatetimepickletokenize
_pydecimaldbmpickletoolstrace
_pyiodecimalpiptraceback
_queuedifflibpipestracemalloc
_randomdispkgutiltty
_sha1distutilsplatformturtle
_sha256doctestplistlibturtledemo
_sha3dummy_threadingpoplibtypes
_sha512emailposixtyping
_signalencodingsposixpathunicodedata
_sitebuiltinsensurepippprintunittest
_socketenumprofileurllib
_sqlite3errnopstatsuu
_srefaulthandlerptvsduuid
_sslfcntlptyvenv
_statfilecmppwdwarnings
_stringfileinputpy_compilewave
_strptimefnmatchpyclbrweakref
_structformatterpydocwebbrowser
_symtablefractionspydoc_datawsgiref
_sysconfigdata_m_linux_x86_64-linux-gnupyexpatxdrlibftplib
_testbufferfunctoolsqueuexml
_testcapigcquoprixmlrpc
_testimportmultiplerandomxxlimitedgenericpath
_testmultiphasegetoptrexxsubtype
_threadgetpassreadlinezipapp
_threading_localgettextreprlibzipfile
_tracemallocglobresourcezipimport
_uuidgrprlcompleterzlib

Tip Run this script in a python-based vRO action to get your own list.

def handler(context, inputs):
	help("modules")
	return None