docs: def from_tuples(cls, tuples):
          """
          Creates a clamping from tuples of the form (variable, sign)
  
          Parameters
          ----------
          tuples : iterable[(str,int)]
              An iterable of tuples describing clamped variables
  
          Returns
          -------
          caspo.core.clamping.Clamping
              Created object instance
          """
          return cls(it.imap(lambda (v, s): Literal(v, s), tuples))