def __init__(self, words=[], tags=[], chunks=[], roles=[], taxa=[], optional=False, multiple=False, first=False, taxonomy=TAXONOMY, exclude=None, custom=None):
self.index    = <NUM_LIT:0><EOL>self.words    = list(words)  <EOL>self.tags     = list(tags)   <EOL>self.chunks   = list(chunks) <EOL>self.roles    = list(roles)  <EOL>self.taxa     = list(taxa)   <EOL>self.taxonomy = taxonomy<EOL>self.optional = optional<EOL>self.multiple = multiple<EOL>self.first    = first<EOL>self.exclude  = exclude      <EOL>self.custom   = custom<EOL>
A range of words, tags and taxonomy terms that matches certain words in a sentence.        
            For example: 
            Constraint.fromstring("with|of") matches either "with" or "of".
            Constraint.fromstring("(JJ)") optionally matches an adjective.
            Constraint.fromstring("NP|SBJ") matches subject noun phrases.
            Constraint.fromstring("QUANTITY|QUALITY") matches quantity-type and quality-type taxa.