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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 dmsStrToDeg(dec):
 """Convert a string representation of DEC into a float in degrees."""

    sign_deg, min, sec = dec.split(':')
    sign = sign_deg[0:1]
    if sign not in ('+', '-'):
        sign = '+'
        deg = sign_deg
    else:
        deg = sign_deg[1:]
    dec_deg = decTimeToDeg(sign, int(deg), int(min), float(sec))
    return dec_deg