import paramiko

def worker_handler(event, context):

    host = "sftpserver.testdpom.com"
    port = 22
    transport = paramiko.Transport((host, port))

    sftp = paramiko.SFTPClient.from_transport(transport)

    username = "xxxx"
    password = "xxxxxx"

    transport.connect(username = username, password = password)

    sftp = paramiko.SFTPClient.from_transport(transport)

    sftp.put("test.txt", "test.txt")
    sftp.close()
    transport.close()

    return
    {
        'message' : "Script execution completed. See Cloudwatch logs for complete output"
    }

File "/var/task/paramiko/kex_group1.py", line 111, in _parse_kexdh_reply
    self.transport._verify_key(host_key, sig)
  File "/var/task/paramiko/transport.py", line 1617, in _verify_key
    key = self._key_info[self.host_key_type](Message(host_key))
  File "/var/task/paramiko/rsakey.py", line 58, in __init__
    ).public_key(default_backend())
  File "/var/task/cryptography/hazmat/backends/__init__.py", line 35, in default_backend
    _default_backend = MultiBackend(_available_backends())
  File "/var/task/cryptography/hazmat/backends/__init__.py", line 22, in _available_backends
    "cryptography.backends"
  File "/var/task/pkg_resources/__init__.py", line 2235, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/var/task/cryptography/hazmat/backends/openssl/__init__.py", line 7, in <module>
    from cryptography.hazmat.backends.openssl.backend import backend
  File "/var/task/cryptography/hazmat/backends/openssl/backend.py", line 15, in <module>
    from cryptography import utils, x509
  File "/var/task/cryptography/x509/__init__.py", line 7, in <module>
    from cryptography.x509.base import (
  File "/var/task/cryptography/x509/base.py", line 15, in <module>
    from cryptography.x509.extensions import Extension, ExtensionType
  File "/var/task/cryptography/x509/extensions.py", line 19, in <module>
    from cryptography.hazmat.primitives import constant_time, serialization
  File "/var/task/cryptography/hazmat/primitives/constant_time.py", line 9, in <module>
    from cryptography.hazmat.bindings._constant_time import lib
ImportError: No module named _constant_time