code: def _validate_dependencies_met():
      
      # Method added in `cryptography==1.1`; not available in older versions
      from cryptography.x509.extensions import Extensions
      if getattr(Extensions, "get_extension_for_class", None) is None:
          raise ImportError("'cryptography' module missing required functionality.  "
                            "Try upgrading to v1.3.4 or newer.")
  
      # pyOpenSSL 0.14 and above use cryptography for OpenSSL bindings. The _x509
      # attribute is only present on those versions.
      from OpenSSL.crypto import X509
      x509 = X509()
      if getattr(x509, "_x509", None) is None:
          raise ImportError("'pyOpenSSL' module missing required functionality. "
                            "Try upgrading to v0.14 or newer.")
docs: Verifies that PyOpenSSL's package-level dependencies have been met.
      Throws `ImportError` if they are not met.