text: # Licensed to the Apache Software Foundation (ASF) under one
  # or more contributor license agreements.  See the NOTICE file
  # distributed with this work for additional information
  # regarding copyright ownership.  The ASF licenses this file
  # to you under the Apache License, Version 2.0 (the
  # "License"); you may not use this file except in compliance
  # with the License.  You may obtain a copy of the License at
  #
  #   http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing,
  # software distributed under the License is distributed on an
  # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  # KIND, either express or implied.  See the License for the
  # specific language governing permissions and limitations
  # under the License.
  # pylint: disable=no-else-return, invalid-name, unused-import
  """The expression nodes of Relay."""
  from __future__ import absolute_import
  
  import tvm._ffi
  from tvm.runtime import convert
  from tvm.ir import BaseFunc
  
  from .expr import Call
  from . import _ffi_api
  
  @tvm._ffi.register_object("relay.Function")
  class Function(BaseFunc):
      """A function declaration expression.
  
      Parameters
      ----------
      params: List[tvm.relay.Var]
          List of input parameters to the function.
  
      body: tvm.relay.Expr
          The body of the function.
  
      ret_type: Optional[tvm.relay.Type]
          The return type annotation of the function.
  
      type_params: Optional[List[tvm.relay.TypeParam]]
          The additional type parameters, this is only
          used in advanced usecase of template functions.
      """
      def __init__(self,
                   params,
                   body,
                   ret_type=None,
                   type_params=None,
                   attrs=None):
          if type_params is None:
              type_params = convert([])
  
          self.__init_handle_by_constructor__(
              _ffi_api.Function, params, body, ret_type, type_params, attrs)
  
      def __call__(self, *args):
          """Invoke the global function.
  
          Parameters
          ----------
          args: List[relay.Expr]
              Arguments.
          """
          return Call(self, args, None, None)
  