Time Code with Microsecond Conversion The function below converts a time code into seconds, while maintaining the decimal value (fractions of seconds). The time code fed to this function will always contain microseconds. This currently works, but I'd be interested to see how it could be improved/simplified.  

def Second_Conversion(x): #Takes a string such as "2:22:04.996304"
    HMS = x.split(':')
    SF = x.split('.')
    Full_HMS = x[0:7]
    Split_HMS = Full_HMS.split(':')

    Full_Units = int(Split_HMS[0]) * 3600 + int(Split_HMS[1]) * 60 + int(Split_HMS[2])


    Second_Fractions = int(SF[1])
    Converted_Seconds_Fractions = Second_Fractions /1000000
    print(Converted_Seconds_Fractions)

    Final_Time = Full_Units + Converted_Seconds_Fractions
    print(Final_Time)
I don't know whether you wanted to optimize the code for length or speed or "elegance", but here it is as a one-liner:

def Second_Conversion(x):
    return sum(map(lambda i,j: int(i)*j, x.replace('.', ':').split(':'), [3600, 60, 1, 1e-6]))