environment/lib/python2.7/site-packages/IPython/core/prefilter.py
def handle(self, line_info):
        # print "normal: ", line_info
        """Handle normal input lines. Use as a template for handlers."""

        # With autoindent on, we need some way to exit the input loop, and I
        # don't want to force the user to have to backspace all the way to
        # clear the line.  The rule will be in this case, that either two
        # lines of pure whitespace in a row, or a line of pure whitespace but
        # of a size different to the indent level, will exit the input loop.
        line = line_info.line
        continue_prompt = line_info.continue_prompt

        if (continue_prompt and
            self.shell.autoindent and
            line.isspace() and
            0 < abs(len(line) - self.shell.indent_current_nsp) <= 2):
            line = ''

        return line
def handle(self, line_info):
        # print "normal: ", line_info
        """Handle normal input lines. Use as a template for handlers."""

        # With autoindent on, we need some way to exit the input loop, and I
        # don't want to force the user to have to backspace all the way to
        # clear the line.  The rule will be in this case, that either two
        # lines of pure whitespace in a row, or a line of pure whitespace but
        # of a size different to the indent level, will exit the input loop.
        line = line_info.line
        continue_prompt = line_info.continue_prompt

        if (continue_prompt and
            self.shell.autoindent and
            line.isspace() and
            0 < abs(len(line) - self.shell.indent_current_nsp) <= 2):
            line = ''

        return line
Handle normal input lines. Use as a template for handlers.