human
Solve the following python programming problem given the following code:
def _scan_pip_requires(self, requires_files) : 
    own_eggs = self._python_eggs (False) 
    def replace_forced_requirements(fn, forced_by_key) : 
        old_lines = sh.load_file (fn).splitlines () 
        new_lines = [] 
        alterations = [] 
        for line in old_lines : 
            try : 
                source_req = pip_helper.extract_requirement (line) 
except (ValueError, TypeError) : 
                pass 
else : 
                if source_req : 
                    validate_requirement (fn, source_req) 
                    try : 
                        replace_req = forced_by_key [source_req.key] 
except KeyError : 
                        pass 
else : 
                        replace_req = str (replace_req) 
                        source_req = str (source_req) 
                        if (replace_req != source_req) : 
                            line = replace_req 
                            alterations.append (('%s => %s' % (colorizer.quote (source_req), colorizer.quote (replace_req)))) 
new_lines.append (line) 
if alterations : 
            contents = ('# Cleaned on %s

%s
' % (utils.iso8601 (), '
'.join (new_lines))) 
            sh.write_file_and_backup (fn, contents) 
            utils.log_iterable (alterations, logger = LOG, header = ('Replaced %s requirements in %s' % (len (alterations), fn)), color = None) 
return len (alterations) 
def on_replace_done(fn, time_taken) : 
        LOG.debug ('Replacing potential forced requirements in %s took %s seconds', colorizer.quote (fn), time_taken) 
def validate_requirement(filename, source_req) : 
        install_egg = None 
        for egg_info in own_eggs : 
            if (egg_info ['name'] == source_req.key) : 
                install_egg = egg_info 
                break 
if (not install_egg) : 
            return 
if (install_egg ['version'] not in source_req) : 
            msg = "Can not satisfy '%s' with '%s', version conflict found in %s" 
            raise exc.DependencyException ((msg % (source_req, install_egg ['req'],...

    
    

    Fix the buggy line: mutations += utils.time_it (functools.partial (on_replace_done, fn), replace_forced_requirements, fn, self)
assistant
#Here is Python code to fix the buggy line: mutations += utils.

mutations += utils.time_it (functools.partial (on_replace_done, fn), replace_forced_requirements, fn, forced_by_key)