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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 insert_blob(filename, hosts=None, table=None):
 """Upload a file into a blob table """

    conn = connect(hosts)
    container = conn.get_blob_container(table)
    with open(filename, 'rb') as f:
        digest = container.put(f)
    return '{server}/_blobs/{table}/{digest}'.format(
        server=conn.client.active_servers[0],
        table=table,
        digest=digest
    )