I have two data frame like this:

```
df1
col1    col2
 A        1
 B        2
 C        3

df2
col1    col2
 E        4
 F        5
 G        6

```

I want to create one data frame by combining these data frames in such a way that one row of df1 followed by one row of df2. 

The desired output is

```
df
col1    col2
 A        1
 E        4
 B        2
 F        5
 C        3
 G        6

```

I could do this using for loop and append the rows into a single data frame from both the data frames, 

But I am looking for pandas shortcuts to do it most efficiently in pythonic way.