capybara/virtualenv/lib/python2.7/site-packages/setuptools/dist.py
def _include_misc(self,name,value):
        """Handle 'include()' for list/tuple attrs without a special handler"""

        if not isinstance(value,sequence):
            raise DistutilsSetupError(
                "%s: setting must be a list (%r)" % (name, value)
            )
        try:
            old = getattr(self,name)
        except AttributeError:
            raise DistutilsSetupError(
                "%s: No such distribution setting" % name
            )
        if old is None:
            setattr(self,name,value)
        elif not isinstance(old,sequence):
            raise DistutilsSetupError(
                name+": this setting cannot be changed via include/exclude"
            )
        else:
            setattr(self,name,old+[item for item in value if item not in old])
def _include_misc(self,name,value):
        """Handle 'include()' for list/tuple attrs without a special handler"""

        if not isinstance(value,sequence):
            raise DistutilsSetupError(
                "%s: setting must be a list (%r)" % (name, value)
            )
        try:
            old = getattr(self,name)
        except AttributeError:
            raise DistutilsSetupError(
                "%s: No such distribution setting" % name
            )
        if old is None:
            setattr(self,name,value)
        elif not isinstance(old,sequence):
            raise DistutilsSetupError(
                name+": this setting cannot be changed via include/exclude"
            )
        else:
            setattr(self,name,old+[item for item in value if item not in old])
Handle 'include()' for list/tuple attrs without a special handler