可能:

>>> import datetime
>>> dt0 = datetime.datetime(1,1,1)
>>> td = datetime.timedelta(minutes=34, hours=12, seconds=56)
>>> (dt0+td).strftime('%X')
'12:34:56'
>>> (dt0+td).strftime('%M:%S')
'34:56'
>>> (dt0+td).strftime('%H:%M')
'12:34'
>>>

Timedelta到字符串，用于打印运行时间信息。

def strfdelta_round(tdelta, round_period='second'):
  """timedelta to string,  use for measure running time
  attend period from days downto smaller period, round to minimum period
  omit zero value period  
  """
  period_names = ('day', 'hour', 'minute', 'second', 'millisecond')
  if round_period not in period_names:
    raise Exception(f'round_period "{round_period}" invalid, should be one of {",".join(period_names)}')
  period_seconds = (86400, 3600, 60, 1, 1/pow(10,3))
  period_desc = ('days', 'hours', 'mins', 'secs', 'msecs')
  round_i = period_names.index(round_period)
  
  s = ''
  remainder = tdelta.total_seconds()
  for i in range(len(period_names)):
    q, remainder = divmod(remainder, period_seconds[i])
    if int(q)>0:
      if not len(s)==0:
        s += ' '
      s += f'{q:.0f} {period_desc[i]}'
    if i==round_i:
      break
    if i==round_i+1:
      s += f'{remainder} {period_desc[round_i]}'
      break
    
  return s

例如，自动省略零前导周期:

>>> td = timedelta(days=0, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'second')
'2 hours 5 mins 8 secs'

或者省略中间的零周期:

>>> td = timedelta(days=2, hours=0, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'millisecond')
'2 days 5 mins 8 secs 3 msecs'

或舍入至分钟，省略以下分钟:

>>> td = timedelta(days=1, hours=2, minutes=5, seconds=8, microseconds=3549)
>>> strfdelta_round(td, 'minute')
'1 days 2 hours 5 mins'

在这里，我会认真考虑奥卡姆剃刀方法:

td = str(timedelta).split('.')[0]

这将返回一个没有微秒的字符串

如果要重新生成datetime。Timedelta对象，只需要这样做:

h,m,s = re.split(':', td)
new_delta = datetime.timedelta(hours=int(h),minutes=int(m),seconds=int(s))

2年了，我爱上了这门语言!

from django.utils.translation import ngettext

def localize_timedelta(delta):
    ret = []
    num_years = int(delta.days / 365)
    if num_years > 0:
        delta -= timedelta(days=num_years * 365)
        ret.append(ngettext('%d year', '%d years', num_years) % num_years)

    if delta.days > 0:
        ret.append(ngettext('%d day', '%d days', delta.days) % delta.days)

    num_hours = int(delta.seconds / 3600)
    if num_hours > 0:
        delta -= timedelta(hours=num_hours)
        ret.append(ngettext('%d hour', '%d hours', num_hours) % num_hours)

    num_minutes = int(delta.seconds / 60)
    if num_minutes > 0:
        ret.append(ngettext('%d minute', '%d minutes', num_minutes) % num_minutes)

    return ' '.join(ret)

这将产生:

>>> from datetime import timedelta
>>> localize_timedelta(timedelta(days=3660, minutes=500))
'10 years 10 days 8 hours 20 minutes'

t1 = datetime.datetime.strptime(StartTime, "%H:%M:%S %d-%m-%y")

t2 = datetime.datetime.strptime(EndTime, "%H:%M:%S %d-%m-%y")

return str(t2-t1)

所以对于:

StartTime = '15:28:53 21-07-13'
EndTime = '15:32:40 21-07-13'

返回:

'0:03:47'

您可以使用str()将timedelta转换为字符串。这里有一个例子:

import datetime
start = datetime.datetime(2009,2,10,14,00)
end   = datetime.datetime(2009,2,10,16,00)
delta = end-start
print(str(delta))
# prints 2:00:00