Anyone help me to fix most_course function ?

# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.

def num_teachers(teachers):
    return len(teachers)
def num_courses(teachers):
    res = 0
    for key in teachers:
        res += len(teachers[key])
    return res
def courses(teachers):
    listT = []
    for value in teachers.values():
        for val in value:
            listT.append(val)
    return listT

def most_courses(teachers):
    maxcourse = 0
    maxname   = ''

    for name in teachers.key():
        if maxcourse < len(teachers[name]): 
            maxcourse = len(teachers[name])
            maxname = name
        else:
            continue
    return maxname