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An automation script reads a multi-document YAML file containing configuration templates for various Junos router models. To process each document individually in Python using PyYAML, which function should the engineer invoke?
2An engineer needs to represent an ordered list of IP addresses in a YAML configuration file for a Junos automation playbook. Which valid YAML syntax correctly defines a sequence of items?
3A Python script retrieves interface statistics from a Junos device in JSON format, modifies a threshold value, and needs to output it back into a formatted JSON string with an indentation level of 4 spaces for readability. Which Python snippet achieves this?
4An automation engineer is writing a Python script that takes a complex nested Python dictionary containing Junos telemetry parameters and converts it into a YAML string. Which PyYAML function should be used?
5A network automation script is reading a YAML configuration file containing Junos device credentials. The script encounters an unhandled exception when attempting to load the file using PyYAML. Upon inspection, the error is caused by a tab character used for indentation instead of spaces. Which YAML specification rule does this violate?
6You are writing a Python automation script that processes JSON output from a Junos device's 'show interfaces' operational command via PyEZ. One of the interface descriptions contains raw control characters. When the script attempts to dump this data to a JSON string using json.dumps(), it raises a ValueError. Which parameter should you pass to json.dumps() to handle non-printable or out-of-range character encoding gracefully?
7Which of the following data types is natively supported in JSON without requiring custom serialization handlers?
8An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a native Python dictionary for internal processing. Which built-in library should the engineer use to convert the structured XML tree?
9Which character is used to indicate a mapping key-value pair in YAML syntax?
10Which file extension is conventionally used for YAML data serialization files?
11Which of the following characters is used to start a comment line in a YAML document?
12A Python script receives a JSON payload from a Junos device containing 64-bit interface counter integers. When loaded using the standard 'json' module, the script experiences precision loss on counter values exceeding standard integer limits. Which alternative JSON parser package for Python should be used to handle high-precision integers without data degradation?
13An automation engineer needs to convert a JSON payload representing Junos interface configurations into equivalent YAML format to reuse in an Ansible playbook. Which fundamental structural relationship between JSON and YAML makes this conversion straightforward?
14An automation scripter needs to load a YAML configuration file in Python. To prevent arbitrary code execution vulnerabilities associated with untrusted files, which function should always be called?
15When converting a deeply nested JSON data structure representing Junos device health metrics into YAML using PyYAML, the output uses complex block styles that are difficult for team members to read. Which parameter in yaml.safe_dump() can force scalar values or containers to prefer flow style (JSON-like curly braces and brackets) instead?
16A Python script reads a Junos configuration snippet stored in YAML. The configuration uses YAML anchors and aliases to duplicate common routing policy definitions across multiple VRFs. When the script parses the file using yaml.safe_load(), what happens to the anchors and aliases?
17What is the primary delimiter used to separate key-value pairs in a JSON object?
18An automation engineer wants to log structured data from a Junos device automation run. The Python script formats a dictionary into a JSON string and prints it. However, the engineer wants all keys sorted alphabetically to ensure consistent log diffing. Which parameter accomplishes this in json.dumps()?
19What type of brackets enclose an array in a JSON document?
20A Python script processes a YAML configuration template for Junos BGP neighbors. The configuration contains a multi-line banner string description. Which YAML block scalar indicator preserves newlines exactly as written in the text block?
21An automation engineer writes a Python script that reads a Junos configuration file serialized in JSON. The file opens successfully, but parsing fails with a JSONDecodeError due to trailing commas at the end of object lists. How does standard JSON handle trailing commas compared to YAML?
22When writing a Python script to interact with a Junos device via PyEZ, you receive an object representing RPC output. You want to serialize a custom Python class instance containing device metadata into JSON, but calling json.dumps() raises a TypeError. What is the standard approach to resolve this?
23An automation script reads a configuration template where boolean values are represented as 'yes' and 'no' in YAML. When parsed using PyYAML in Python, how are these values interpreted?
24You are writing a Python automation script that reads a Junos configuration file in JSON format. The JSON file contains duplicate keys within the same object scope. According to the JSON specification RFC 8259, how should a conforming JSON parser handle duplicate keys?
25Which Python module is part of the standard library and provides functions to serialize and deserialize JSON data?
26Which symbol represents the beginning of a single YAML document stream?
27An automation engineer is writing a script that saves operational telemetry data gathered from a Junos router. The data needs to be written directly to an open file stream in JSON format. Which method from the Python 'json' module should be used?
28When parsing a Junos configuration snippet in YAML, an engineer notices a string value starting with a zero (e.g., '01234') that is unquoted. How do YAML parsers typically interpret this value?
29An engineer needs to convert an existing YAML-formatted inventory file into JSON format using a Python script. Which workflow accomplishes this transformation?
30You are writing a Python automation tool that reads telemetry data from a Junos device. The data is received as a JSON string containing forward slashes escaped as '\/'. When you load this string using json.loads(), how does Python handle the escaped slashes?
31An automation engineer is writing a Python script to push configurations to a Junos device. The script loads a YAML data file containing interface descriptions. One description contains a colon without a following space (e.g., 'Interface:Primary'). What error will PyYAML raise when attempting to parse this file?
32Which Python function deserializes a JSON-formatted string into a native Python dictionary?
33Which of the following describes the fundamental structural difference between JSON and YAML regarding syntax design?
34A Python automation script parses a Junos telemetry stream in JSON. The JSON payload uses integer keys in a dictionary (e.g., {443: 'HTTPS'}). When loaded into Python using json.loads(), what data type do the dictionary keys become?
35An automation engineer needs to include comments explaining complex network parameters inside a Junos automation data file. Which serialization format should the engineer select?
36You are writing a Python script that parses a multi-document YAML stream containing Junos device site configurations. One of the documents contains a custom YAML tag. When parsing with yaml.safe_load_all(), how does the safe loader handle custom tags?
37Which of the following valid JSON values represents a boolean true state?
38What is the native data format returned by Junos devices when queried via REST API or NETCONF operations configured with JSON output formatting?
39An automation engineer wants to verify the syntax of a large YAML playbook before executing it against a production Junos device. Which python one-liner command can be run in the terminal to quickly check if the file is syntactically valid YAML?
40A Python automation script extracts routing table entries from a Junos device. The data structure contains deeply nested dictionaries and lists. The engineer needs to perform a deep copy of this deserialized JSON structure before modifying it. Which Python module provides the deepcopy function needed to duplicate nested containers safely?
41An automation script reads interface names and VLAN IDs from a CSV file and converts each row into a JSON object before sending it to a Junos device REST API. Which Python module is specifically designed to parse CSV (Comma-Separated Values) files?
42You are writing a Python script that converts a Junos operational state output from XML (via NETCONF) into JSON. The XML structure contains sibling elements with the same tag name. When converted naively, how do standard XML-to-JSON conversion libraries (like xmltodict) typically represent these repeated sibling elements in the resulting JSON dictionary?
43Which of the following primitive data types is NOT supported natively in JSON?
44Which TWO of the following are valid primitive data types in JSON? (Choose two)
45An automation engineer needs to pretty-print a JSON payload in the Linux terminal for debugging Junos telemetry. Which built-in Python command-line utility can be invoked to validate and pretty-print a JSON file?
46You are writing a Python automation script that processes configuration data. The script reads a YAML file containing Junos firewall filters, modifies them, and writes them back out. However, you notice that all the original comments in the file are stripped out in the output. What is the fundamental reason for this behavior in standard PyYAML dump operations?
47Which TWO of the following are valid extensions commonly used for YAML files? (Choose two)
48Which TWO methods are provided by the Python standard library 'json' module for deserializing JSON data? (Choose two)
49When working with PyYAML in Python for Junos automation scripts, which THREE of the following practices enhance script security and robustness? (Choose three)
50Which TWO features are supported by YAML but are notably absent in standard JSON? (Choose two)
51When serializing Python data structures to JSON for Junos automation payloads, which THREE parameters can be passed to json.dumps() to control formatting and readability? (Choose three)
52Which TWO of the following are valid scalar values in a YAML document? (Choose two)
53Which TWO Python standard library modules are commonly combined when a script needs to fetch web content (such as Junos REST API data) and parse the resulting payload? (Choose two)
54Which TWO characters or sequences are valid in YAML for representing lists or sequences? (Choose two)
55When serializing complex nested Python dictionaries to JSON, which THREE data types will cause a TypeError unless handled by a custom default encoder function? (Choose three)
56When writing an automation script that converts data formats between YAML and JSON for Junos configuration pipelines, which THREE potential pitfalls should an engineer account for? (Choose three)
57Which TWO Python exceptions might be raised when attempting to parse a malformed JSON string using the standard 'json' module? (Choose two)
58An automation engineer is writing a Python script to parse a Juniper Junos NETCONF reply received in XML format and needs to convert it into a JSON structure for easier manipulation in a web application. Which built-in Python module is primarily used to handle JSON data serialization and deserialization?
59An engineer receives a YAML configuration snippet for a PyEZ automation script, but the script fails with a parser error. Upon inspection, the error is caused by improper indentation levels. Which rule must be strictly followed regarding indentation in YAML syntax?
60You are writing a Python script using the PyEZ library to retrieve interface facts from a Juniper EX Series switch. The resulting data structure is stored in a Python dictionary. You need to dump this dictionary into a YAML file so it can be read by an Ansible playbook later. Which PyYAML function should you use to convert the Python dictionary into a YAML-formatted string or file stream?
61An automation developer is examining a JSON response payload returned by a Juniper device via a REST API call. Which valid JSON data type is used to represent an ordered list of values enclosed within square brackets?
62During script development, an engineer encounters a YAML file containing comments and multiple configuration documents separated by document markers. Which characters are used to denote the start of a new document within a single YAML file stream?
63An automation script needs to convert a JSON string containing Juniper interface statistics into a YAML format to maintain consistency with existing Ansible variable files. When performing this conversion, which structural capability does YAML support that standard JSON does not?
64An automation engineer is reviewing data serialization formats used within Junos automation workflows. Which TWO statements are correct regarding JSON syntax and data types? (Choose two)
65You are writing a Python script to convert a complex Juniper device inventory from YAML format into JSON format using PyYAML and the built-in json module. Which THREE considerations must you keep in mind regarding differences between YAML and JSON during this conversion? (Choose three)
66An engineer writes a Python script that loads a JSON configuration file using the json.load() method. The file contains configuration parameters for a Junos device. If the JSON file contains a trailing comma at the end of the last element in an array, what will happen when the script executes?
67An automation developer is designing a script that reads routing policy parameters from a configuration file. Which TWO data formats are natively supported and commonly used across Junos automation toolchains like PyEZ, Ansible, and REST APIs for data serialization? (Choose two)
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