numpy_string_array.py

In [1]: import numpy as np                                                                                                                                                  

In [2]: X = ["One", "string"]                                                                                                                                               

In [3]: X                                                                                                                                                                   
Out[3]: ['One', 'string']

In [4]: X[0]                                                                                                                                                                
Out[4]: 'One'

In [5]: type(X[0])                                                                                                                                                          
Out[5]: str

In [6]: X = np.array(X)                                                                                                                                                     

In [7]: X                                                                                                                                                                   
Out[7]: array(['One', 'string'], dtype='<U6')

In [8]: X[1] = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"                                                                                                               

In [9]: X                                                                                                                                                                   
Out[9]: array(['One', 'xxxxxx'], dtype='<U6')

In [10]: X = X.astype(object)                                                                                                                                               

In [11]: X                                                                                                                                                                  
Out[11]: array(['One', 'xxxxxx'], dtype=object)

In [12]: X[1]  = "yyyyyyyyyyyyyyyyyy"                                                                                                                                       

In [13]: X                                                                                                                                                                  
Out[13]: array(['One', 'yyyyyyyyyyyyyyyyyy'], dtype=object)