import re


def strip_str(base_value):
    """Convert value to string and strips special characters.

    None becomes empty string
    """
    base_string = str(base_value)
    if base_string == 'None':
        return ''
    else:
        strip_special_chars = re.sub(r'[()<>/"\,\'\\]', '', base_string)
        return str(strip_special_chars)