class DBConnection(object):
    def __init__(self, driver, serve,
                 database, user, password):

        self.driver = driver
        self.server = server
        self.database = database
        self.user = user
        self.password = password

    def __enter__(self):
        self.dbconn = pyodbc.connect("DRIVER={};".format(self.driver) +
                                     "SERVER={};".format(self.server) +
                                     "DATABASE={};".format(self.database) +
                                     "UID={};".format(self.user) +
                                     "PWD={};".format(self.password) +
                                     "CHARSET=UTF8",
                                     # "",
                                     ansi=True)

        return self.dbconn

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.dbconn.close()

def get_database_connection():
     conn = DBConnection.connection
     if not conn:
          conn = DBConnection.connection = DBConnection.create_connection()
     return conn