How to create a dictionary of key : column_name and value : unique values in column in python from a dataframe

I am trying to create a dictionary of key:value pairs where key is the column name of a dataframe and value will be a list containing all the unique values in that column.Ultimately I want to be able to filter out the key_value pairs from the dict based on conditions. This is what I have been able to do so far:

for col in col_list[1:]:
    _list = []
    _list.append(footwear_data[col].unique())
    list_name = ''.join([str(col),'_list'])

product_list = ['shoe','footwear']
color_list = []
size_list = []

Here product,color,size are all column names and the dict keys should be named accordingly like color_list etc. Ultimately I will need to access each key:value_list in the dictionary. Expected output:

KEY              VALUE
color_list :    ["red","blue","black"]
size_list:  ["9","XL","32","10 inches"]

Can someone please help me regarding this?A snapshot of the data is attached.