import pandas as pd

df1 = pd.DataFrame(
    {
        "writer": ["kadowaki", "terada", "takanory"],
        "value": [1, 2, 3],
    }
)
df2 = pd.DataFrame(
    {
        "writer": ["ryu22e", "fukuda"],
        "value": [4, 5],
    }
)
print(pd.concat([df1, df2]))