def count_beans(beans):
    '''Return a list giving the number of beans of each color.
    Each entry of the returned list is a two-element list
    consisting of the color and the count of that color.'''
    color_counts = []
    for color in beans:
        found_color = False
        for color_count_pair in color_counts:
            if color_count_pair[0] == color:
                found_color = True
                color_count_pair[1] += 1 # increase existing counter for this color
        
        if not found_color: # first bean of this color, add a new entry
            color_counts.append([color, 1])
            
    return color_counts

def count_beans_v2(beans):
    '''Return a dictionary mapping colors to the number of beans
    of that color.'''
    color_counts = {}
    for color in beans:
        if color in color_counts: # is color an existing key of the dictionary?
            color_counts[color] += 1 # updating an existing key/value pair
        else:
            color_counts[color] = 1 # adding a new key/value pair
    return color_counts

def count_beans_v3(beans):
    '''Return a dictionary mapping colors to the number of beans
    of that color.'''
    color_counts = {}
    for color in beans:
        color_counts[color] = color_counts.get(color, 0) + 1         
    return color_counts

##############################

def count_values(some_dict):
    '''Return the number of unique values in the dictionary.'''
    values_set = set()
    for key in some_dict:
        values_set.add(some_dict[key])
    return len(values_set)

def count_values_v2(some_dict):
    '''Return the number of unique values in the dictionary.'''
    values_set = set()
    for value in some_dict.values():
        values_set.add(value)
    return len(values_set)

def count_values_v3(some_dict):
    '''Return the number of unique values in the dictionary.'''
    return len(set(some_dict.values()))