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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Topology
This caterogy of questions is intended to retrieve the network topology
used by Batfish. This topology is a combination of information in the
snapshot and inference logic (e.g., which interfaces are layer3 neighbors).
Currently, Layer 3 topology can be retrieved.
User Provided Layer 1 Topology
Layer 3 Topology
Step1:  User Provided Layer 1 Topology
Returns normalized Layer 1 edges that were input to Batfish.
Lists Layer 1 edges after potentially normalizing node and interface names. All node names are lower-cased, and for nodes that appear in the snapshot, interface names are canonicalized based on the vendor. All input edges are in the output, including nodes and interfaces that do not appear in the snapshot.
Inputs
Name | Description | Type | Optional | Default Value
--- | --- | --- | --- | --- 
nodes | Include edges whose first node matches this name or regex. | NodeSpec | True | .
remoteNodes | Include edges whose second node matches this name or regex. | NodeSpec | True | .
Invocation
Step2:  Return Value
Name | Description | Type
--- | --- | ---
Interface | Interface from which the edge originates | Interface
Remote_Interface | Interface at which the edge terminates | Interface
Print the first 5 rows of the returned Dataframe
Step3:  Print the first row of the returned Dataframe
Step4:  Layer 3 Topology
Returns Layer 3 links.
Lists all Layer 3 edges in the network.
Inputs
Name | Description | Type | Optional | Default Value
--- | --- | --- | --- | --- 
nodes | Include edges whose first node matches this name or regex. | NodeSpec | True | .
remoteNodes | Include edges whose second node matches this name or regex. | NodeSpec | True | .
Invocation
Step5:  Return Value
Name | Description | Type
--- | --- | ---
Interface | Interface from which the edge originates | Interface
IPs | IPs | Set of str
Remote_Interface | Interface at which the edge terminates | Interface
Remote_IPs | Remote IPs | Set of str
Print the first 5 rows of the returned Dataframe
Step6:  Print the first row of the returned Dataframe
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Python Code:
bf.set_network('generate_questions')
bf.set_snapshot('aristaevpn')
Explanation: Topology
This caterogy of questions is intended to retrieve the network topology
used by Batfish. This topology is a combination of information in the
snapshot and inference logic (e.g., which interfaces are layer3 neighbors).
Currently, Layer 3 topology can be retrieved.
User Provided Layer 1 Topology
Layer 3 Topology
End of explanation
result = bf.q.userProvidedLayer1Edges().answer().frame()
Explanation: User Provided Layer 1 Topology
Returns normalized Layer 1 edges that were input to Batfish.
Lists Layer 1 edges after potentially normalizing node and interface names. All node names are lower-cased, and for nodes that appear in the snapshot, interface names are canonicalized based on the vendor. All input edges are in the output, including nodes and interfaces that do not appear in the snapshot.
Inputs
Name | Description | Type | Optional | Default Value
--- | --- | --- | --- | --- 
nodes | Include edges whose first node matches this name or regex. | NodeSpec | True | .
remoteNodes | Include edges whose second node matches this name or regex. | NodeSpec | True | .
Invocation
End of explanation
result.head(5)
Explanation: Return Value
Name | Description | Type
--- | --- | ---
Interface | Interface from which the edge originates | Interface
Remote_Interface | Interface at which the edge terminates | Interface
Print the first 5 rows of the returned Dataframe
End of explanation
result.iloc[0]
bf.set_network('generate_questions')
bf.set_snapshot('generate_questions')
Explanation: Print the first row of the returned Dataframe
End of explanation
result = bf.q.layer3Edges().answer().frame()
Explanation: Layer 3 Topology
Returns Layer 3 links.
Lists all Layer 3 edges in the network.
Inputs
Name | Description | Type | Optional | Default Value
--- | --- | --- | --- | --- 
nodes | Include edges whose first node matches this name or regex. | NodeSpec | True | .
remoteNodes | Include edges whose second node matches this name or regex. | NodeSpec | True | .
Invocation
End of explanation
result.head(5)
Explanation: Return Value
Name | Description | Type
--- | --- | ---
Interface | Interface from which the edge originates | Interface
IPs | IPs | Set of str
Remote_Interface | Interface at which the edge terminates | Interface
Remote_IPs | Remote IPs | Set of str
Print the first 5 rows of the returned Dataframe
End of explanation
result.iloc[0]
Explanation: Print the first row of the returned Dataframe
End of explanation
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