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PoC implementation:
from enum import Enum
import ssl
OP_NO_TLSv1_3 = getattr(ssl, 'OP_NO_TLSv1_3', 0)
OP_NO_FLAGS = [
 ssl.OP_NO_SSLv2,
 ssl.OP_NO_SSLv3,
 ssl.OP_NO_TLSv1,
 ssl.OP_NO_TLSv1_1,
 ssl.OP_NO_TLSv1_2,
 OP_NO_TLSv1_3
]
OP_NO_MASK = sum(OP_NO_FLAGS)
class TLSVersions(Enum):
 SSLv2 = 'SSL 2.0', 0x0200, 0
 SSLv3 = 'SSL 3.0', 0x0300, 1
 TLSv1 = 'TLS 1.0', 0x0301, 2
 TLSv1_1 = 'TLS 1.1', 0x0302, 3
 TLSv1_2 = 'TLS 1.2', 0x0303, 4
 if OP_NO_TLSv1_3:
 TLSv1_3 = 'TLS 1.3', 0x0304, 5
 MAX = TLSv1_3
 else:
 MAX = TLSv1_2
 MIN = TLSv1
 def __init__(self, prettyname, wireprotocol, offset):
 self.prettyname = prettyname
 self.wireprotocol = wireprotocol
 self.noflag = OP_NO_FLAGS[offset]
 self.minflag = sum(OP_NO_FLAGS[:offset])
 self.maxflag = sum(OP_NO_FLAGS[offset+1:])
 def __repr__(self):
 return ("<{0.__class__.__name__}.{0.name} "
 "({0.prettyname}, 0x{0.wireprotocol:x})>").format(self)
 __str__ = __repr__
class SSLContext(ssl.SSLContext):
 def set_version(self, minver=TLSVersions.MIN, maxver=TLSVersions.MAX):
 options = self.options & ~OP_NO_MASK
 self.options = options | minver.minflag | maxver.maxflag
if __name__ == '__main__':
 for name, member in TLSVersions.__members__.items():
 print(name, member)
 ctx = SSLContext(ssl.PROTOCOL_SSLv23)
 print(ctx.options)
 ctx.set_version(minver=TLSVersions.SSLv3, maxver=TLSVersions.TLSv1_1)
 print(ctx.options)