how to add a column to a dataframe from another data code example

Example 1: how to add a column to a pandas df

#using the insert function:
df.insert(location, column_name, list_of_values) 
#example
df.insert(0, 'new_column', ['a','b','c'])
#explanation:
#put "new_column" as first column of the dataframe
#and puts 'a','b' and 'c' as values

#using array-like access:
df['new_column_name'] = value

#df stands for dataframe

Example 2: python how to add columns to a pandas dataframe

# Basic syntax:
pandas_dataframe['new_column_name'] = ['list', 'of', 'column', 'values']

# Note, the list of column values must have length equal to the number
# 	of rows in the pandas dataframe you are adding it to.

# Add column in which all rows will be value:
pandas_dataframe['new_column_name'] = value
# Where value can be a string, an int, a float, and etc