Sequence as string

>>> seq1 = "MMSARGDFLN"
>>> seq2 = "YALSLMRSHN"
>>> seq = seq1 + seq2
>>> print seq
MMSARGDFLNYALSLMRSHN
>>> print seq[0]
M
>>> print seq[:5]
MMSAR
>>> print seq[-3:]
SHN
>>>

>>> seq + 7
Traceback (most recent call last):
  File "", line 1, in ?
TypeError: cannot concatenate 'str' and 'int' objects
>>> 

 
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