utc = pytz.utc
eastern = pytz.timezone('US/Eastern')
fmt = '%Y-%m-%d %H:%M:%S %Z%z'
text = """10/1/2010   0:0:0
10/1/2010   0:6:0
10/1/2010   23:54:0
10/3/2010   0:0:0
"""
for datestring in text.splitlines():
    date = dt.datetime.strptime(datestring, '%m/%d/%Y %H:%M:%S')
date_eastern = eastern.localize(date, is_dst=None)
date_utc = date_eastern.astimezone(utc)
print(date_utc.strftime(fmt))
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