remove mapstructure from identity,networking,objectstorage,orchestration,pagination
diff --git a/openstack/networking/v2/extensions/external/results.go b/openstack/networking/v2/extensions/external/results.go
index c5d5f14..2c5173a 100644
--- a/openstack/networking/v2/extensions/external/results.go
+++ b/openstack/networking/v2/extensions/external/results.go
@@ -1,7 +1,6 @@
 package external
 
 import (
-	"github.com/mitchellh/mapstructure"
 	"github.com/gophercloud/gophercloud/openstack/networking/v2/networks"
 	"github.com/gophercloud/gophercloud/pagination"
 )
@@ -10,72 +9,69 @@
 // "external-net" extension.
 type NetworkExternal struct {
 	// UUID for the network
-	ID string `mapstructure:"id" json:"id"`
+	ID string `json:"id"`
 
 	// Human-readable name for the network. Might not be unique.
-	Name string `mapstructure:"name" json:"name"`
+	Name string `json:"name"`
 
 	// The administrative state of network. If false (down), the network does not forward packets.
-	AdminStateUp bool `mapstructure:"admin_state_up" json:"admin_state_up"`
+	AdminStateUp bool `json:"admin_state_up"`
 
 	// Indicates whether network is currently operational. Possible values include
 	// `ACTIVE', `DOWN', `BUILD', or `ERROR'. Plug-ins might define additional values.
-	Status string `mapstructure:"status" json:"status"`
+	Status string `json:"status"`
 
 	// Subnets associated with this network.
-	Subnets []string `mapstructure:"subnets" json:"subnets"`
+	Subnets []string `json:"subnets"`
 
 	// Owner of network. Only admin users can specify a tenant_id other than its own.
-	TenantID string `mapstructure:"tenant_id" json:"tenant_id"`
+	TenantID string `json:"tenant_id"`
 
 	// Specifies whether the network resource can be accessed by any tenant or not.
-	Shared bool `mapstructure:"shared" json:"shared"`
+	Shared bool `json:"shared"`
 
 	// Specifies whether the network is an external network or not.
-	External bool `mapstructure:"router:external" json:"router:external"`
-}
-
-func commonExtract(e error, response interface{}) (*NetworkExternal, error) {
-	if e != nil {
-		return nil, e
-	}
-
-	var res struct {
-		Network *NetworkExternal `json:"network"`
-	}
-
-	err := mapstructure.Decode(response, &res)
-
-	return res.Network, err
+	External bool `json:"router:external"`
 }
 
 // ExtractGet decorates a GetResult struct returned from a networks.Get()
 // function with extended attributes.
 func ExtractGet(r networks.GetResult) (*NetworkExternal, error) {
-	return commonExtract(r.Err, r.Body)
+	var s struct {
+		Network *NetworkExternal `json:"network"`
+	}
+	err := r.ExtractInto(&s)
+	return s.Network, err
 }
 
 // ExtractCreate decorates a CreateResult struct returned from a networks.Create()
 // function with extended attributes.
 func ExtractCreate(r networks.CreateResult) (*NetworkExternal, error) {
-	return commonExtract(r.Err, r.Body)
+	var s struct {
+		Network *NetworkExternal `json:"network"`
+	}
+	err := r.ExtractInto(&s)
+	return s.Network, err
 }
 
 // ExtractUpdate decorates a UpdateResult struct returned from a
 // networks.Update() function with extended attributes.
 func ExtractUpdate(r networks.UpdateResult) (*NetworkExternal, error) {
-	return commonExtract(r.Err, r.Body)
+	var s struct {
+		Network *NetworkExternal `json:"network"`
+	}
+	err := r.ExtractInto(&s)
+	return s.Network, err
 }
 
 // ExtractList accepts a Page struct, specifically a NetworkPage struct, and
 // extracts the elements into a slice of NetworkExternal structs. In other
 // words, a generic collection is mapped into a relevant slice.
 func ExtractList(page pagination.Page) ([]NetworkExternal, error) {
-	var resp struct {
-		Networks []NetworkExternal `mapstructure:"networks" json:"networks"`
+	r := page.(networks.NetworkPage)
+	var s struct {
+		Networks []NetworkExternal `json:"networks" json:"networks"`
 	}
-
-	err := mapstructure.Decode(page.(networks.NetworkPage).Body, &resp)
-
-	return resp.Networks, err
+	err := r.ExtractInto(&s)
+	return s.Networks, err
 }