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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _str_datetime_now(self, x=None):
 """Return datetime string for use with time attributes. Handling depends on input: 'now' - returns datetime for now number - assume datetime values, generate string other - no change, return same value """

        if (x == 'now'):
            # Now, this is wht datetime_to_str() with no arg gives
            return(datetime_to_str())
        try:
            # Test for number
            junk = x + 0.0
            return datetime_to_str(x)
        except TypeError:
            # Didn't look like a number, treat as string
            return x