LTSVをpandasに読み込む ref: https://qiita.com/yuba/items/0a9c8be19e32a00547e5

file0.txt

host:example.com    url:/api/users  status:200  time:2018-01-01T00:00:00+09:00
host:example.com    url:/api/users  status:200  time:2018-01-01T00:00:01+09:00

file1.txt

from collections import OrderedDict
import pandas as pd

def ltsv_to_data_frame(filename):
    """
    LTSVファイルを読み込んでpandas DataFrameを生成します
    値はすべて文字列型となります
    """
    with open(filename) as f:
        return pd.DataFrame(
            [OrderedDict(cell.split(':', 1)
                         for cell
                         in line.rstrip('\r\n').split('\t'))
             for line in f])

file2.txt

from io import StringIO  # Python2の場合は from cStringIO

tsv = ltsv_to_data_frame(filename).to_csv(sep='\t', index=False)
df = pd.read_table(StringIO(tsv))