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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _ensure_dependency_available_at_version(package_name, min_version):
 """Throw helpful error if required dependencies not available."""


  try:
    pkg = importlib.import_module(package_name)
  except ImportError:
    pip_name = package_name.replace('_', '-')
    raise SystemError(
        'Sonnet requires %s (minimum version %s) to be installed. '
        'If using pip, run `pip install %s` or '
        '`pip install %s-gpu`' % (
            package_name, min_version, pip_name, pip_name))

  installed_version = semantic_version.Version(pkg.__version__)
  version_spec = semantic_version.Spec('>=' + min_version)
  if not version_spec.match(installed_version):
    raise SystemError(
        '%s version %s is installed, but Sonnet requires at least version %s.' %
        (package_name, pkg.__version__, min_version))