Teachers.py problem with task 4

# 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(dict):
  number_teachers=0
  for key in dict.keys():
    number_teachers += 1
  return number_teachers

def num_courses(dict):
  number_courses=0
  for value in dict.values():
    number_courses += len(value)
  return number_courses

 def courses(dict):
  name_courses=[]
  for value in dict.values():
    name_courses += value)
  return name_courses


def most_courses(dic):
    max_count = 0
    teacher_most_classes = " "
    for key in dic:
        if len(dic[key]) > max_count:
            max_count = len(dic[key])
            teacher_most_classes = key
    return teacher_most_classes