class Employee(...):
    Attributes:
        @type username: str
            ...
        @type password: str
            ...

class Database(...):
    Attributes:
        @type employees: dict {str : str}
            A dictionary of employees, using their names as keys, and their
            save path as the value.

    def log_in(self, username, password):
        for e in self.employees:
            employee = dill.load(open(self.employees[e], "rb"))
            ...
        # Checks all employees in database, breaks when provided username &
        # password matches saved username & password

class LogInFrame(...):
    ...
    def __init__(self, db):
        # loads the database
        self.database = db
        ...