parameters: (cls, value, lineno=None, environment=None)
return_statement: return cls(value, lineno=lineno, environment=environment)
docstring: Return a const object if the value is representable as
          constant value in the generated code, otherwise it will raise
          an `Impossible` exception.
docstring_summary: Return a const object if the value is representable as
          constant value in the generated code, otherwise it will raise
          an `Impossible` exception.
docstring_tokens: Return a const object if the value is representable as constant value in the generated code otherwise it will raise an Impossible exception .
function: def from_untrusted(cls, value, lineno=None, environment=None):
          """Return a const object if the value is representable as
          constant value in the generated code, otherwise it will raise
          an `Impossible` exception.
          """
          from .compiler import has_safe_repr
          if not has_safe_repr(value):
              raise Impossible()
          return cls(value, lineno=lineno, environment=environment)
function_tokens: def from_untrusted ( cls , value , lineno = None , environment = None ) : from . compiler import has_safe_repr if not has_safe_repr ( value ) : raise Impossible ( ) return cls ( value , lineno = lineno , environment = environment )