code: def solve_each(expr, vars):
      
      lhs_values, _ = __solve_for_repeated(expr.lhs, vars)
  
      for lhs_value in repeated.getvalues(lhs_values):
          result = solve(expr.rhs, __nest_scope(expr.lhs, vars, lhs_value))
          if not result.value:
              # Each is required to return an actual boolean.
              return result._replace(value=False)
  
      return Result(True, ())
docs: Return True if RHS evaluates to a true value with each state of LHS.
  
      If LHS evaluates to a normal IAssociative object then this is the same as
      a regular let-form, except the return value is always a boolean. If LHS
      evaluates to a repeared var (see efilter.protocols.repeated) of
      IAssociative objects then RHS will be evaluated with each state and True
      will be returned only if each result is true.