How to add my data to a python pandas data frame from a dictionary?

I am trying to add data to a python dataframe from multiple dictionary items, then operate on that data within the dataframe.

Here is my code below with the desired outcome:

import numpy as np
import pandas as pd

from numpy.random import randn

mylist = [('Jane', 20), ('Helen', 30), ('Jack', 40)]
mydict_one = {'Jane' : 10, 'Helen' : 15, 'Jack' : 20}
mydict_two = {'Jane' : 30, 'Helen' : 45, 'Jack' : 60}


df = pd.DataFrame([], [items[0] for items in mylist], ['mydict_one', 'mydict_two', 'subtracted_value'])
print(df)

The desired outcome after adding the data would be as such:

       mydict_one  mydict_two  subtracted_value
Jane     10        30          20
Helen    15        45          30
Jack     20        60          40

I hope my question is clear enough.

Answer

We can convert mylist to a dict, build the DataFrame and transpose:

df = pd.DataFrame(
    [mydict_one, mydict_two, dict(mylist)],
    index=['mydict_one', 'mydict_two', 'subtracted_value']  # "Column names"
).T  # Transpose

df:

       mydict_one  mydict_two  subtracted_value
Jane           10          30                20
Helen          15          45                30
Jack           20          60                40

We can also calculate subtracted value instead of using mylist:

df = pd.DataFrame(
    [mydict_one, mydict_two],
    index=['mydict_one', 'mydict_two']  # "Column names"
).T  # Transpose

df['subtracted_value'] = df['mydict_two'] - df['mydict_one']

df:

       mydict_one  mydict_two  subtracted_value
Jane           10          30                20
Helen          15          45                30
Jack           20          60                40