Method to set a MySQL connection

    :param str host: MySQL database host
    :param str user: MySQL database user
    :param str passwd: MySQL database password
    :param str db: MySQL database name
    :param str charset: MySQL database charater set

    :return: connection string
    :rtype: str

def set_mysql_connection(host='localhost', user='pyhgnc_user', passwd='pyhgnc_passwd', db='pyhgnc',
                         charset='utf8'):
    """Method to set a MySQL connection

    :param str host: MySQL database host
    :param str user: MySQL database user
    :param str passwd: MySQL database password
    :param str db: MySQL database name
    :param str charset: MySQL database charater set

    :return: connection string
    :rtype: str
    """
    connection_string = 'mysql+pymysql://{user}:{passwd}@{host}/{db}?charset={charset}'.format(
        host=host,
        user=user,
        passwd=passwd,
        db=db,
        charset=charset
    )
    set_connection(connection_string)

    return connection_string