How To Make Gant Charts Using Plotly

Assume That We Have A Spreadsheet Containing A List Of Tasks Like This

TASK	START	FINISH
TASK A	2021-03-25	2021-03-31
TASK B	2021-03-25	2021-03-31
TASK C	2021-03-31	2021-04-15
TASK D	2021-04-02	2021-04-22
TASK E	2021-04-01	2021-04-05
TASK F	2021-04-22	2021-04-26
TASK G	2021-04-27	2021-05-15H        

Since We Are Using Python3 On Google Colaboratory, We Will Need To Have Access To Google Drive Through Google Colab First, This Could Be Achieved Using This Snippet Of Code.

from?google.colab?import?driv
drive.mount('/content/drive')e        

In Our Case We Are Not Uploading An Excel File To Google Colab, So We Will Not Use The Pandas pd.read_excel , However , We Will Use The Following Snippets

import?plotly.express?as?px
import?pandas?as?pd
from?google.colab?import?aut
auth.authenticate_user()
import?gspread
from?oauth2client.client?import?GoogleCredentialsh        

gc?=?gspread.authorize(GoogleCredentials.get_application_default()


worksheet?=?gc.open('dummy?for?gant?chart?colab').sheet1


#?get_all_values?gives?a?list?of?rows.
rows?=?worksheet.get_all_values()
print(rows)
#?Convert?to?a?DataFrame?and?render.
pd.DataFrame.from_records(rows)
df1?=?pd.DataFrame.from_records(rows))        

We Will Then Rename The Pandas Data Frame To Drop The First Index Row Using This Snippet

#droping?first?row?"index?row"?then?renaming?the?new?data?frame
df1.rename(columns=df1.iloc[0]).drop(df1.index[0])
df2?=?df1.rename(columns=df1.iloc[0]).drop(df1.index[0])?        

Now We Are Ready To Visualize Our Gant Chart

fig?=?px.timeline(df2,?x_start="START",?x_end="FINISH",?y="TASK"
fig.update_yaxes(autorange="reversed")?#?otherwise?tasks?are?listed?from?the?bottom?up
fig.show()        

The Google Colab Note Book Is Down In The First Comment.