src/streamlink/plugin/api/validate.py
def startswith(string):
    """Checks if the string value starts with another string."""
    def starts_with(value):
        validate(text, value)
        if not value.startswith(string):
            raise ValueError("'{0}' does not start with '{1}'".format(value, string))
        return True

    return starts_with
def startswith(string):
    """Checks if the string value starts with another string."""
    def starts_with(value):
        validate(text, value)
        if not value.startswith(string):
            raise ValueError("'{0}' does not start with '{1}'".format(value, string))
        return True

    return starts_with
Checks if the string value starts with another string.