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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:
 async def graphql( schema: GraphQLSchema, source: Union[str, Source], root_value: Any = None, context_value: Any = None, variable_values: Dict[str, Any] = None, operation_name: str = None, field_resolver: GraphQLFieldResolver = None, type_resolver: GraphQLTypeResolver = None, middleware: Middleware = None, execution_context_class: Type[ExecutionContext] = ExecutionContext, ) -> ExecutionResult: """Execute a GraphQL operation asynchronously. This is the primary entry point function for fulfilling GraphQL operations by parsing, validating, and executing a GraphQL document along side a GraphQL schema. More sophisticated GraphQL servers, such as those which persist queries, may wish to separate the validation and execution phases to a static time tooling step, and a server runtime step. Accepts the following arguments: :arg schema: The GraphQL type system to use when validating and executing a query. :arg source: A GraphQL language formatted string representing the requested operation. :arg root_value: The value provided as the first argument to resolver functions on the top level type (e.g. the query object type). :arg context_value: The context value is provided as an attribute of the second argument (the resolve info) to resolver functions. It is used to pass shared information useful at any point during query execution, for example the currently logged in user and connections to databases or other services. :arg variable_values: A mapping of variable name to runtime value to use for all variables defined in the request string. :arg operation_name: The name of the operation to use if request string contains multiple possible operations. Can be omitted if request string contains only one operation. :arg field_resolver: A resolver function to use when one is not provided by the schema. If not provided, the default field resolver is used (which looks for a value or method on the source value with the field's name). :arg type_resolver: A type resolver function to use when none is provided by the schema. If not provided, the default type resolver is used (which looks for a `__typename` field or alternatively calls the `isTypeOf` method). :arg middleware: The middleware to wrap the resolvers with :arg execution_context_class: The execution context class to use to build the context """

    # Always return asynchronously for a consistent API.
    result = graphql_impl(
        schema,
        source,
        root_value,
        context_value,
        variable_values,
        operation_name,
        field_resolver,
        type_resolver,
        middleware,
        execution_context_class,
    )

    if isawaitable(result):
        return await cast(Awaitable[ExecutionResult], result)

    return cast(ExecutionResult, result)