def __init__(self, attrs=None):
attrs = attrs or []<EOL>self.attrs = list(attrs)<EOL>if ORTH in self.attrs:<EOL><INDENT>self.attrs.pop(ORTH)<EOL><DEDENT>if SPACY in self.attrs:<EOL><INDENT>self.attrs.pop(SPACY)<EOL><DEDENT>self.attrs.insert(<NUM_LIT:0>, ORTH)<EOL>self.tokens = []<EOL>self.spaces = []<EOL>self.strings = set()<EOL>
Create a Binder object, to hold serialized annotations.

        attrs (list): List of attributes to serialize. 'orth' and 'spacy' are
            always serialized, so they're not required. Defaults to None.