how to merge two dataframes vertically in pandas code example

Example 1: how to merge two dictionaries in python

>>> x = {'a': 1, 'b': 2}
>>> y = {'b': 10, 'c': 11}
>>> z = {**x, **y} #In Python 3.5 or greater only
>>> print(z)
{'a': 1, 'b': 10, 'c': 11}

Example 2: split pandas dataframe in two

df_new1, df_new2 = df[:10, :], df[10:, :] if len(df) > 10 else df, None