I have three dataframe as below:
import pandas as pd
labels=['1','2','3','Aggregated']
df1 = {'date_time': ["2022-10-06 17:23:11","2022-10-06 17:23:12","2022-10-06 17:23:13","2022-10-06 17:23:14","2022-10-06 17:23:15","2022-10-06 17:23:16"],
'value': [4, 5, 6, 7, 8, 9]}
df2 = {'date_time': ["2022-10-06 17:23:13","2022-10-06 17:23:14","2022-10-06 17:23:15","2022-10-06 17:23:16","2022-10-06 17:23:17","2022-10-06 17:23:18"],
'value': [4, 5, 6, 7, 8, 9]}
df3 = {'date_time': ["2022-10-06 17:23:16","2022-10-06 17:23:17","2022-10-06 17:23:18","2022-10-06 17:23:19","2022-10-06 17:23:20","2022-10-06 17:23:21"],
'value': [4, 5, 6, 7, 8, 9]}
I need to create another dataframe df that contains all the datetime elements from all three df1,df2,df3 such that the common valued are summed up in-terms of common timestamps (excluding the millisecond parts) as shown below.
df=
{'date_time': ["2022-10-06 17:23:11","2022-10-06 17:23:12","2022-10-06 17:23:13","2022-10-06 17:23:14","2022-10-06 17:23:15","2022-10-06 17:23:16","2022-10-06 17:23:17","2022-10-06 17:23:18","2022-10-06 17:23:19","2022-10-06 17:23:20","2022-10-06 17:23:21"],
'value': [4, 5, 6+4, 7+5, 8+6, 9+7+4, 8+5, 9+6, 7, 8, 9]}
For adding the columns I used following:
df = (pd.concat([df1,df2,df3],axis=0)).groupby('date_time')['value'].sum().reset_index()
For plotting I used following which results in df2 and df3 to time shift towards df1.
for dataFrame,number in zip([df1,df2,df3,df],labels):
dataFrame["value"].plot(label=number)
How can I plot the three df1,df2,df3 without time shifting and also plot the aggregated df on the same plot for dataframe column 'value'?

labels?