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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:
 def get_session(user_agent):
 """Sets up urllib sessions"""


    client = requests.Session()
    client.headers.update({
        'Content-Type': 'application/json',
        'User-Agent': user_agent,
    })
    retry = Retry(connect=3, backoff_factor=3)
    adapter = HTTPAdapter(max_retries=retry)
    client.mount('https://', adapter)
    return client